feat: add promoted template edit contracts (#3407)

* feat: add promoted template edit contracts

* fix: address template contract review feedback

registry/blocks/ai-chat-reveal/TEMPLATE.md

@@ -0,0 +1,19 @@
+# AI Chat Reveal editing contract
+
+## Surface ownership
+
+This is a generic assistant conversation followed by a brandable closing card. The website brand may appear in the declared conversation and closing-card slots; the chat shell and motion remain template-owned.
+
+## Editable slots
+
+Only defaults declared in `data-composition-variables` are editable:
+
+- `botName`, `userMessage`, `answer1` through `answer3`
+- `bullet1` through `bullet3`
+- `ecHeadline`, `ecSub`, `ecCta`, and `ecFooter`
+
+Typed and streamed copy is length-locked to within 20% of the original.
+
+## Protected
+
+Do not change chat chrome, keyboard, layout, logo asset, palette, fonts, scene order, duration, timing, easing, typing cadence, or reveal logic. This contract declares no image or color variables.

registry/blocks/ai-chat-reveal/registry-item.json

@@ -119,6 +119,11 @@
       "path": "assets/hyperframes-logo-white.svg",
       "target": "assets/hyperframes-logo-white.svg",
       "type": "hyperframes:asset"
+    },
+    {
+      "path": "TEMPLATE.md",
+      "target": "TEMPLATE.md",
+      "type": "hyperframes:asset"
     }
   ]
 }