share: render markdown + preview-before-publish + soul-history probe

Share card now displays the AI bubble's marked-rendered HTML (after
basic tag allowlist sanitization) instead of escaped plaintext.
Markdown bold, lists, code, headers all show.

Share click in chat now opens a preview modal. Publishing to the
gallery only happens when the user explicitly clicks Publish in the
modal - removes the click-and-immediately-public surprise.

src/assets/js/manifest.json

@@ -1,6 +1,6 @@
 {
   "generated_by": "scripts/extract-js.py",
-  "count": 11,
+  "count": 12,
   "entries": [
     {
       "file": "account.el",
@@ -50,6 +50,14 @@
       "interpolated": [],
       "note": "carried from prior run"
     },
+    {
+      "file": "gallery.el",
+      "hash": "d8251f5e5aa1",
+      "asset": "/assets/js/d8251f5e5aa1.js",
+      "size": 12354,
+      "interpolated": [],
+      "note": "carried from prior run"
+    },
     {
       "file": "main.el",
       "hash": "94727a87c328",
@@ -74,6 +82,13 @@
       "interpolated": [],
       "note": "carried from prior run"
     },
+    {
+      "file": "styles.el",
+      "hash": "37b5ead0d425",
+      "asset": "/assets/js/37b5ead0d425.js",
+      "size": 23539,
+      "interpolated": []
+    },
     {
       "file": "styles.el",
       "hash": "407e72cd7182",
@@ -81,14 +96,6 @@
       "size": 6430,
       "interpolated": [],
       "note": "carried from prior run"
-    },
-    {
-      "file": "styles.el",
-      "hash": "fc247ef45b1d",
-      "asset": "/assets/js/fc247ef45b1d.js",
-      "size": 18624,
-      "interpolated": [],
-      "note": "carried from prior run"
     }
   ]
 }