Add ISAC mechanic gap handoff actions

docs/architecture.md

@@ -484,6 +484,17 @@ The model returns one structured result:
   representation, an optional workaround, and the schema, runtime, editor,
   reference, and test changes a developer would need to add support.
 
+For a mechanic capability gap, the client builds a developer prompt from the
+exact analyzed wording, clarification transcript, source profile, and
+structured gap response. The author can copy that prompt without another model
+request. The author can also submit the gap to active full administrators.
+The submission endpoint validates bounded fields, confirms that the request ID
+belongs to the author's audited `capability_gap` generation, suppresses repeat
+submissions, sends mandatory ISAC notifications, and appends a
+`mechanic_gap.submitted` event to the `ai_assistance` audit category. The
+notification links to the filtered audit evidence. Submission does not mutate
+the mechanic draft or parent game-data record.
+
 The server validates `draft_ready` output against the response schema and the
 same deterministic mechanic parser used by manual authoring. Unknown events,
 Attributes, value models, scopes, operators, reducers, or outcomes fail