chore(runtime): snapshot the LIVE darwin soul runtime (el-sdk) into git

Verbatim capture of ~/el-sdk/el_runtime.{c,h} — the un-versioned source the live
macOS soul (:7770, 765760B) is actually built from. Captured so the data-integrity
fixes that exist ONLY in this file are no longer one rm away from gone with no history.

Contains (vs origin/main): the UAF fix (engram_node_full uses el_strdup_persist —
the hallucinated/lost-saves root cause; 27 sites vs 19) and the response-truncation
fix (max(strlen,_tl_fs_read_len) binary-safe reads).

DIVERGES BOTH WAYS: this snapshot LACKS main's newer engram_wm_*, engram_load_merge,
http_serve_async (diff is deletion-heavy as a result) and still lacks the atomic
engram_save (temp+fsync+rename) fix. DO NOT merge over main — reconcile by porting
the two fixes above forward onto main.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lang/el-compiler/runtime/el_runtime.c

@@ -1475,10 +1475,13 @@ static void http_send_response(int fd, const char* body) {
     }
 
     const char* eff_body = is_envelope ? env_body : body;
-    /* Use the real byte count from fs_read if available (handles binary files
-     * with embedded null bytes — PNG, WOFF2, etc.). Fall back to strlen for
-     * normal text/JSON responses where _tl_fs_read_len is 0. */
-    size_t blen = (_tl_fs_read_len > 0) ? _tl_fs_read_len : strlen(eff_body);
+    /* Use max(strlen, fs_read_len). fs_read_len is the real byte count for binary
+     * files (strlen stops at embedded NULs — PNG, WOFF2). strlen is correct AND larger
+     * when a handler WRAPS fs_read output in a longer text/JSON response (e.g.
+     * /api/safety-contact returns {"configured":...,"contact": <file>}); using
+     * fs_read_len alone truncated those responses to the file's length. */
+    size_t _blen_s = strlen(eff_body);
+    size_t blen = (_tl_fs_read_len > _blen_s) ? _tl_fs_read_len : _blen_s;
     _tl_fs_read_len = 0;  /* consume — one-shot per response */
     int head_only = _tl_http_head_only;
 
@@ -1552,7 +1555,8 @@ static void* http_worker(void* arg) {
             /* Copy response out BEFORE arena teardown.
              * For binary files, _tl_fs_read_len holds the real byte count —
              * use memcpy instead of strdup so null bytes are preserved. */
-            size_t rlen = _tl_fs_read_len > 0 ? _tl_fs_read_len : (rs ? strlen(rs) : 0);
+            size_t _rlen_s = rs ? strlen(rs) : 0;
+            size_t rlen = (_tl_fs_read_len > _rlen_s) ? _tl_fs_read_len : _rlen_s;
             response = malloc(rlen + 1);
             if (response && rs) { memcpy(response, rs, rlen); response[rlen] = '\0'; }
             else if (response) { response[0] = '\0'; }
@@ -1799,7 +1803,8 @@ static void* http_worker_v2(void* arg) {
             el_val_t hmap = http_build_headers_map(hdr_block ? hdr_block : "");
             el_val_t r = h(EL_STR(dispatch_method), EL_STR(path), hmap, EL_STR(body));
             const char* rs = EL_CSTR(r);
-            size_t rlen = _tl_fs_read_len > 0 ? _tl_fs_read_len : (rs ? strlen(rs) : 0);
+            size_t _rlen_s = rs ? strlen(rs) : 0;
+            size_t rlen = (_tl_fs_read_len > _rlen_s) ? _tl_fs_read_len : _rlen_s;
             response = malloc(rlen + 1);
             if (response && rs) { memcpy(response, rs, rlen); response[rlen] = '\0'; }
             else if (response) { response[0] = '\0'; }
@@ -3173,23 +3178,49 @@ static void jb_puts(JsonBuf* b, const char* s) {
 
 static void jb_emit_escaped(JsonBuf* b, const char* s) {
     jb_putc(b, '"');
-    for (; *s; s++) {
-        unsigned char c = (unsigned char)*s;
+    const unsigned char* p = (const unsigned char*)s;
+    while (*p) {
+        unsigned char c = *p;
         switch (c) {
-            case '"':  jb_puts(b, "\\\""); break;
-            case '\\': jb_puts(b, "\\\\"); break;
-            case '\b': jb_puts(b, "\\b");  break;
-            case '\f': jb_puts(b, "\\f");  break;
-            case '\n': jb_puts(b, "\\n");  break;
-            case '\r': jb_puts(b, "\\r");  break;
-            case '\t': jb_puts(b, "\\t");  break;
+            case '"':  jb_puts(b, "\\\""); p++; break;
+            case '\\': jb_puts(b, "\\\\"); p++; break;
+            case '\b': jb_puts(b, "\\b");  p++; break;
+            case '\f': jb_puts(b, "\\f");  p++; break;
+            case '\n': jb_puts(b, "\\n");  p++; break;
+            case '\r': jb_puts(b, "\\r");  p++; break;
+            case '\t': jb_puts(b, "\\t");  p++; break;
             default:
                 if (c < 0x20) {
                     char tmp[8];
                     snprintf(tmp, sizeof(tmp), "\\u%04x", c);
                     jb_puts(b, tmp);
-                } else {
+                    p++;
+                } else if (c < 0x80) {
                     jb_putc(b, (char)c);
+                    p++;
+                } else {
+                    /* Multi-byte UTF-8: validate sequence, pass through if valid,
+                     * escape as \u00xx if the start byte is invalid/orphaned. */
+                    int seq_len = 0;
+                    if      ((c & 0xE0) == 0xC0) seq_len = 2;
+                    else if ((c & 0xF0) == 0xE0) seq_len = 3;
+                    else if ((c & 0xF8) == 0xF0) seq_len = 4;
+                    if (seq_len >= 2) {
+                        int valid = 1;
+                        for (int i = 1; i < seq_len; i++) {
+                            if ((p[i] & 0xC0) != 0x80) { valid = 0; break; }
+                        }
+                        if (valid) {
+                            for (int i = 0; i < seq_len; i++) jb_putc(b, (char)p[i]);
+                            p += seq_len;
+                            break;
+                        }
+                    }
+                    /* Invalid start byte or truncated sequence — escape it */
+                    char tmp[8];
+                    snprintf(tmp, sizeof(tmp), "\\u%04x", c);
+                    jb_puts(b, tmp);
+                    p++;
                 }
                 break;
         }
@@ -6219,7 +6250,9 @@ static void engram_grow_edges(void) {
 static char* engram_new_id(void) {
     el_val_t v = uuid_new();
     const char* s = EL_CSTR(v);
-    return el_strdup(s ? s : "");
+    /* Persistent: node ids live in the global store; an arena (el_strdup) id is
+     * freed at el_request_end(), corrupting the node after the creating request. */
+    return el_strdup_persist(s ? s : "");
 }
 
 /* Convert a node into an ElMap of its fields.                            */
@@ -6314,12 +6347,17 @@ el_val_t engram_node_full(el_val_t content, el_val_t node_type, el_val_t label,
     const char* lb = EL_CSTR(label);
     const char* ti = EL_CSTR(tier);
     const char* tg = EL_CSTR(tags);
-    n->content   = el_strdup(c ? c : "");
-    n->node_type = el_strdup(nt && *nt ? nt : "Memory");
-    n->label     = el_strdup(lb && *lb ? lb : (c ? engram_first_n_chars(c, 60) : ""));
-    n->tier      = el_strdup(ti && *ti ? ti : "Working");
-    n->tags      = el_strdup(tg ? tg : "");
-    n->metadata  = el_strdup("{}");
+    /* Persistent (el_strdup_persist, NOT el_strdup): these strings are owned by the
+     * persistent global node store. el_strdup tracks into the per-request arena, which
+     * el_request_end() frees when the creating HTTP request completes — leaving the
+     * stored node with dangling pointers (corrupted ids, "saved but never listed").
+     * This is the root cause of the hallucinated/lost-saves class of bugs. */
+    n->content   = el_strdup_persist(c ? c : "");
+    n->node_type = el_strdup_persist(nt && *nt ? nt : "Memory");
+    n->label     = el_strdup_persist(lb && *lb ? lb : (c ? engram_first_n_chars(c, 60) : ""));
+    n->tier      = el_strdup_persist(ti && *ti ? ti : "Working");
+    n->tags      = el_strdup_persist(tg ? tg : "");
+    n->metadata  = el_strdup_persist("{}");
     n->salience    = engram_decode_score(salience);
     n->importance  = engram_decode_score(importance);
     n->confidence  = engram_decode_score(confidence);