feat: auto-capture Claude Code sessions via Stop hook

Add deploy/hooks/capture_stop.py — a Claude Code Stop hook that reads
the transcript JSONL, extracts the last user prompt, and POSTs to the
AtoCore /interactions endpoint in conservative mode (reinforce=false).

Conservative mode means: capture only, no automatic reinforcement or
extraction into the review queue. Kill switch: ATOCORE_CAPTURE_DISABLED=1.

Also: note build_sha cosmetic issue after restore in runbook, update
project status docs to reflect drill pass and auto-capture wiring.

17 new tests (243 total, all passing).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docs/next-steps.md

@@ -20,24 +20,14 @@ This working list should be read alongside:
 
 ## Immediate Next Steps
 
-1. Re-run the backup/restore drill on Dalidou with the Chroma
-   bind-mount fix in place
-   - the 2026-04-09 drill was a PARTIAL PASS: db restore + marker
-     reversal worked cleanly, but the Chroma step failed with
-     `OSError [Errno 16] Device or resource busy` because
-     `shutil.rmtree` cannot unlink a Docker bind-mounted volume
-   - fix landed immediately after: `restore_runtime_backup()` now
-     clears the destination's CONTENTS and uses
-     `copytree(dirs_exist_ok=True)`, and the regression test
-     `test_restore_chroma_does_not_unlink_destination_directory`
-     asserts the destination inode is stable
-   - need a green end-to-end run with `--chroma` actually
-     working in-container before enabling write-path automation
-2. Turn on auto-capture of Claude Code sessions once the drill
-   re-run is clean
-   - conservative mode: Stop hook posts to `/interactions`,
-     no auto-extraction into review queue without review cadence
-     in place
+1. ~~Re-run the backup/restore drill~~ — DONE 2026-04-11, full pass
+2. ~~Turn on auto-capture of Claude Code sessions~~ — DONE 2026-04-11,
+   Stop hook via `deploy/hooks/capture_stop.py` → `POST /interactions`
+   with `reinforce=false`; kill switch: `ATOCORE_CAPTURE_DISABLED=1`
+2a. Run a short real-use pilot with auto-capture on
+   - verify interactions are landing in Dalidou
+   - check prompt/response quality and truncation
+   - confirm fail-open: no user-visible impact when Dalidou is down
 3. Use the T420 `atocore-context` skill and the new organic routing layer in
    real OpenClaw workflows
    - confirm `auto-context` feels natural