feat(mcp): add openWorldHint to all tool annotations

ChatGPT Apps submission requires all three hints (readOnlyHint,
destructiveHint, openWorldHint) set explicitly; we only had the first two.
openWorldHint mirrors read_only: write tools act on external social platforms
(publish/send/manage) so they touch the open world; GET tools only read and
don't change external state. Set in the generator (294 tools) and the
@tool_def decorator (20 custom tools); regenerated. Verified 0/314 missing.

Also gitignore the chatgpt-app-submission.json artifact (generated for the
submission form, not source).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: mikipalet

.gitignore

@@ -81,3 +81,4 @@ Thumbs.db
 
 # Project specific
 *.log
+chatgpt-app-submission.json

scripts/generate_mcp_tools.py

@@ -423,11 +423,16 @@ def generate_tool_handler(
     # Strip trailing whitespace from all docstring lines
     docstring = "\n    ".join(line.rstrip() for line in doc_lines)
 
-    # Tool annotation (Anthropic Connectors Directory requirement). title is
-    # rendered via repr() so quotes/specials in the summary are escaped safely.
+    # Tool annotation (required by the Anthropic Connectors Directory AND the
+    # ChatGPT Apps submission, which needs all three hints set explicitly).
+    # title is rendered via repr() so quotes/specials in the summary are
+    # escaped safely. openWorldHint mirrors read_only: write tools act on
+    # external social platforms (publish/send/etc.) so they touch the open
+    # world; GET tools only read, so they don't change external state.
     annotation = (
         f"annotations=ToolAnnotations(title={title!r}, "
-        f"readOnlyHint={read_only}, destructiveHint={not read_only})"
+        f"readOnlyHint={read_only}, destructiveHint={not read_only}, "
+        f"openWorldHint={not read_only})"
     )
 
     lines.append("")