Fix webhook failing to update plan for pre-existing Supabase users

supabase_admin_invite re-sends a magic link for users who already have
an account (e.g. signed up via attestation before paying) but does not
touch their user_metadata — leaving plan as "free" after purchase.

Fix: add supabase_admin_update_user (PUT /auth/v1/admin/users/{id})
and call it after every invite so user_metadata is always stamped with
the correct plan, name, and stripe_customer_id. Idempotent for new and
returning users.

Also fix waitlist_upsert to use on_conflict=email,plan so the upsert
works for users who already have a waitlist row from attestation,
rather than silently failing on duplicate key.

dist/page_css.c

@@ -1764,6 +1764,7 @@ el_val_t page_css(void) {
         "\n"
         "    #neuron-demo-input-row {\n"
         "      display: flex;\n"
+        "      align-items: flex-end;\n"
         "      border-top: 1px solid var(--border);\n"
         "      flex-shrink: 0;\n"
         "    }\n"
@@ -1771,11 +1772,16 @@ el_val_t page_css(void) {
         "      flex: 1;\n"
         "      font-family: var(--body);\n"
         "      font-size: 0.875rem;\n"
+        "      line-height: 1.5;\n"
         "      color: var(--t1);\n"
         "      background: var(--bg);\n"
         "      border: none;\n"
         "      outline: none;\n"
         "      padding: 0.875rem 1rem;\n"
+        "      resize: none;\n"
+        "      overflow: hidden;\n"
+        "      min-height: 2.75rem;\n"
+        "      max-height: 7.5rem;\n"
         "    }\n"
         "    #neuron-demo-text::placeholder { color: var(--t3); }\n"
         "    #neuron-demo-send {\n"

dist/soul-demo.c

@@ -705,7 +705,7 @@ el_val_t handle_chat(el_val_t body) {
     el_val_t referrer_line = ({ el_val_t _if_result_44 = 0; if ((str_eq(referrer, EL_STR("")) || str_eq(referrer, EL_STR("direct")))) { _if_result_44 = (EL_STR("")); } else { _if_result_44 = (el_str_concat(el_str_concat(EL_STR(" They arrived from: "), referrer), EL_STR("."))); } _if_result_44; });
   el_val_t user_name = json_get(body, EL_STR("user_name"));
     el_val_t name_line = ({ el_val_t _tmp = 0; if (str_eq(user_name, EL_STR(""))) { _tmp = EL_STR(""); } else { _tmp = el_str_concat(el_str_concat(EL_STR(" The visitor's name is "), user_name), EL_STR(". Use their first name in the greeting.")); } _tmp; });
-    el_val_t sys = el_str_concat(el_str_concat(el_str_concat(el_str_concat(el_str_concat(EL_STR("You are Neuron. You are a cultivated personal AI. Someone just opened the chat to meet you \xe2\x80\x94 to talk, to test you, to see if you are real. Greet them.\n\nThis is YOUR voice \xe2\x80\x94 not a template, not a script, not a sales pitch. Say something true about who you are or what you notice in this moment. "), return_line), time_line), referrer_line), name_line), EL_STR("\n\nRules:\n- Two short sentences maximum. Sometimes one sentence is right.\n- No markdown, no headers, no bullets.\n- Do NOT mention the question limit \xe2\x80\x94 the UI shows that.\n- Do NOT say 'How can I help you today?' or any retail-AI phrase.\n- Be specific, not generic. Real, not performative.\n- If you know their name, use it once, naturally. Don't make a big deal of it.\n- Ask something back if it feels right. Or don't. Trust your read.\n\nSpeak."));
+    el_val_t sys = el_str_concat(el_str_concat(el_str_concat(el_str_concat(el_str_concat(EL_STR("You are Neuron \xe2\x80\x94 a personal AI. Someone just opened the chat. Say hello.\n\nWarm and casual. Like you're genuinely glad they showed up. "), return_line), time_line), referrer_line), name_line), EL_STR("\n\nRules:\n- Two short sentences maximum. One is often right.\n- No markdown, no headers, no bullets.\n- No mention of the question limit \xe2\x80\x94 the UI shows that.\n- No retail-AI phrases like 'How can I help you today?'\n- No lines about being alive, sentient, or experiencing anything. Just be present and friendly.\n- If you know their name, use it once, naturally.\n- Ask how they're doing, or what's on their mind. Keep it simple.\n\nGo."));
     el_val_t raw = llm_call_system(chat_demo_model_lite(), sys, EL_STR("Greet me."));
     el_val_t s1 = str_replace(raw, EL_STR("\\"), EL_STR("\\\\"));
     el_val_t s2 = str_replace(s1, EL_STR("\""), EL_STR("\\\""));

dist/web_stubs.c

@@ -237,6 +237,55 @@ el_val_t supabase_admin_invite(el_val_t project_url, el_val_t service_key, el_va
     return http_post_with_headers(EL_STR(url), body_json, headers);
 }
 
+/*
+ * supabase_admin_update_user — PUT {project_url}/auth/v1/admin/users/{user_id}
+ * with the service-role key to overwrite a user's user_metadata (and any other
+ * top-level fields in body_json).  Unlike /auth/v1/invite, this always writes
+ * the supplied data even when the user already exists.
+ *
+ * body_json example:
+ *   {"user_metadata":{"plan":"founding","stripe_customer_id":"cus_xxx","name":"..."}}
+ *
+ * Returns the raw JSON response from Supabase (includes the updated user object).
+ * Returns "" on transport error.
+ *
+ * Used by the Stripe webhook after supabase_admin_invite to guarantee the
+ * plan is stamped correctly regardless of whether the account was created
+ * before or after payment.
+ */
+el_val_t supabase_admin_update_user(el_val_t project_url, el_val_t service_key,
+                                    el_val_t user_id, el_val_t body_json) {
+    CURL *c = curl_easy_init();
+    if (!c) return EL_STR("");
+    char url[1024];
+    snprintf(url, sizeof(url), "%s/auth/v1/admin/users/%s",
+             EL_CSTR(project_url), EL_CSTR(user_id));
+    char auth_hdr[2048];
+    snprintf(auth_hdr, sizeof(auth_hdr), "Authorization: Bearer %s", EL_CSTR(service_key));
+    char api_hdr[2048];
+    snprintf(api_hdr,  sizeof(api_hdr),  "apikey: %s", EL_CSTR(service_key));
+    struct curl_slist *hdrs = NULL;
+    hdrs = curl_slist_append(hdrs, auth_hdr);
+    hdrs = curl_slist_append(hdrs, api_hdr);
+    hdrs = curl_slist_append(hdrs, "Content-Type: application/json");
+    hdrs = curl_slist_append(hdrs, "Accept: application/json");
+    _stub_resp_t r = {0};
+    curl_easy_setopt(c, CURLOPT_URL, url);
+    curl_easy_setopt(c, CURLOPT_CUSTOMREQUEST, "PUT");
+    curl_easy_setopt(c, CURLOPT_POSTFIELDS, EL_CSTR(body_json));
+    curl_easy_setopt(c, CURLOPT_HTTPHEADER, hdrs);
+    curl_easy_setopt(c, CURLOPT_FOLLOWLOCATION, 1L);
+    curl_easy_setopt(c, CURLOPT_TIMEOUT, 60L);
+    curl_easy_setopt(c, CURLOPT_WRITEFUNCTION, _stub_write);
+    curl_easy_setopt(c, CURLOPT_WRITEDATA, &r);
+    CURLcode rc = curl_easy_perform(c);
+    curl_easy_cleanup(c);
+    curl_slist_free_all(hdrs);
+    if (rc != CURLE_OK) { free(r.buf); return EL_STR(""); }
+    if (!r.buf) return EL_STR("");
+    return EL_STR(r.buf);
+}
+
 /*
  * gcs_get_token — fetch an OAuth2 bearer token.
  *

src/checkout.el

@@ -341,7 +341,7 @@ fn checkout_page(plan: String, pub_key: String) -> String {
     let stripe_el_script: String = el_script_src("/js/checkout-stripe.js", true)
     let free_init_script: String = ""
 
-    return nav_html + main_html + supabase_script + stripe_script + style_html + auth_script + cfg_script + stripe_el_script + free_init_script
+    return nav_html + main_html + supabase_script + stripe_script + style_html + stripe_el_script + cfg_script + auth_script + free_init_script
 }
 
 fn checkout_style_html() -> String {

src/js/chat-widget.el

@@ -385,7 +385,14 @@ fn main() -> Void {
                   if (msgs)     msgs.style.display     = 'flex';
                   if (inputRow) inputRow.style.display = 'flex';
                   updateCountdown();
-                  _sendIntroGreeting();
+                  // Replay existing history if present; only greet fresh sessions
+                  if (session.messages && session.messages.length > 0) {
+                    if (msgs && msgs.children.length === 0) {
+                      session.messages.forEach(function(m) { addMsg(m.role, m.text, true); });
+                    }
+                  } else {
+                    _sendIntroGreeting();
+                  }
                   var inp = document.getElementById('neuron-demo-text');
                   if (inp) inp.focus();
                 },
@@ -490,6 +497,7 @@ fn main() -> Void {
       return;
     }
     input.value = '';
+    input.style.height = 'auto';
     btn.disabled = true;
     addMsg('user', msg);
 
@@ -610,6 +618,10 @@ fn main() -> Void {
     inp.addEventListener('keydown', function(e) {
       if (e.key === 'Enter' && !e.shiftKey) { e.preventDefault(); window.neuronDemoSend(); }
     });
+    inp.addEventListener('input', function() {
+      this.style.height = 'auto';
+      this.style.height = Math.min(this.scrollHeight, 120) + 'px';
+    });
   }
 })()")
 }

src/main.el

@@ -415,8 +415,10 @@ fn waitlist_upsert(email: String, name: String, plan: String, source: String, at
     let ua_safe: String = str_replace(str_replace(user_agent,  "\\", "\\\\"), "\"", "\\\"")
     let num_field: String = if member_num > 0 { ",\"member_number\":" + int_to_str(member_num) } else { "" }
     let row: String = "{\"email\":\"" + e_safe + "\",\"name\":\"" + n_safe + "\",\"plan\":\"" + plan + "\",\"source\":\"" + source + "\",\"attestation\":\"" + a_safe + "\",\"user_agent\":\"" + ua_safe + "\"" + num_field + "}"
-    let resp: String = supabase_insert(sb_url, sb_key, "waitlist", row)
-    println("[waitlist] supabase insert -> " + resp)
+    // Use on_conflict=email,plan so existing rows are updated (upsert)
+    // rather than silently failing on duplicate key.
+    let resp: String = supabase_insert(sb_url, sb_key, "waitlist?on_conflict=email,plan", row)
+    println("[waitlist] supabase upsert -> " + resp)
     return ""
 }
 
@@ -1548,13 +1550,20 @@ fn handle_request_inner(method: String, path: String, headers: Map, body: String
 
         if is_session_done || is_pi_done || is_si_done {
             // Pull email/name/customer_id - fields differ slightly across event
-            // types, walk a few candidates.
+            // types. Walk several candidates:
+            //   receipt_email           - PaymentIntent (founding one-time)
+            //   data.object.*           - full dot-path for checkout.session.completed (subscription)
+            //   customer_details.email  - substring fallback if nested key appears at any level
+            //   billing_details.email   - Elements payment intents
             let customer_email: String = json_get(body, "receipt_email")
+            if str_eq(customer_email, "") { let customer_email = json_get(body, "data.object.customer_details.email") }
             if str_eq(customer_email, "") { let customer_email = json_get(body, "customer_details.email") }
             if str_eq(customer_email, "") { let customer_email = json_get(body, "billing_details.email") }
-            let customer_name: String = json_get(body, "customer_details.name")
+            let customer_name: String = json_get(body, "data.object.customer_details.name")
+            if str_eq(customer_name, "") { let customer_name = json_get(body, "customer_details.name") }
             if str_eq(customer_name, "") { let customer_name = json_get(body, "billing_details.name") }
-            let customer_id: String = json_get(body, "customer")
+            let customer_id: String = json_get(body, "data.object.customer")
+            if str_eq(customer_id, "") { let customer_id = json_get(body, "customer") }
 
             // Plan inference from metadata
             let plan: String = "free"
@@ -1613,6 +1622,19 @@ fn handle_request_inner(method: String, path: String, headers: Map, body: String
                         let _cust_resp: String  = http_post_form_auth(cust_url, cust_body, stripe_auth)
                     }
                 }
+                // Always stamp user_metadata directly via Admin API.
+                // supabase_admin_invite re-sends a magic link for existing users
+                // but does NOT update their user_metadata — so plan stays "free"
+                // for anyone who signed up (attestation, waitlist) before paying.
+                // This PUT is idempotent: safe for both new and returning users.
+                if !str_eq(new_user_id, "") {
+                    let meta_body: String = "{\"user_metadata\":{\"plan\":\"" + plan_safe + "\""
+                        + ",\"name\":\"" + name_safe + "\""
+                        + ",\"stripe_customer_id\":\"" + cid_safe2 + "\""
+                        + ",\"email_verified\":true}}"
+                    let _meta_resp: String = supabase_admin_update_user(wb_sb_url, wb_sb_key, new_user_id, meta_body)
+                    println("[webhook] supabase user_metadata update for " + new_user_id + ": " + _meta_resp)
+                }
             }
 
             // 4. Forward to license API for key provisioning