docs: land prior ADR + prompt updates

Commit pre-existing uncommitted working-tree changes that predate the
license/public-readiness work — NOT authored in this session, just flushed so
they're not lost: ADR-0003/0005/0009/0012 edits, the new ADR-0013
(embeddings-bypass + two-slot residency, already referenced by CLAUDE.md), and
the phase-0..3 prompt revisions + prompts/README.md.

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

docs/adr/0005-webhook-protocol.md

@@ -22,7 +22,7 @@ that URL on every state transition.
   "state": "loading",
   "previous_state": "queued",
   "timestamp": "2026-05-23T12:00:00Z",
-  "model": "qwen3.6:35b",
+  "model": "qwen3:30b",
   "attempt": 1,
   "error": null,
   "result": null,
@@ -59,5 +59,6 @@ that URL on every state transition.
 
 - **Polling only.** Simpler for foreman, worse for callers; rejected since
   webhooks were an explicit requirement. (Polling is still available as fallback.)
-- **WebSocket/SSE for state.** Heavier; SSE is reserved for token streaming on the
-  sync surface (ADR-0012), not job-state fan-out.
+- **WebSocket/streamed connection for state.** Heavier; token streaming on the
+  sync surface is NDJSON (ADR-0012), and job-state fan-out doesn't need a
+  persistent connection — discrete webhook POSTs suffice.