docs(observer): HK1 pre-check noted in README (ADR-010 compliance)

Verified Stop event collision before B5 registration:
- User-level (~/.claude/settings.json): Stop hook = agent-type
  Sonnet-4.6 economy compliance verifier (already wired in
  6-component arch).
- Project-level (.claude/settings.json): Stop slot empty.

observer-stop-hook will register as command-type entry in
project-level Stop array. Independent slot from user-level agent;
no overwrite, no collision. Per Pravila ADR-010 HK1 hard-rule.

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

docs/observer/README.md

@@ -25,3 +25,12 @@ PII filter (phone numbers, emails, tokens) is applied **before** every write —
 - Don't edit `episodes-*.jsonl` manually — it's append-only.
 - Don't write outside `docs/observer/notes/` for hand-curated notes.
 - Don't change `.read-counter.json` manually — it's maintained by hooks.
+
+## HK1 pre-check (Pravila ADR-010) — verified 2026-05-19
+
+Before registering `tools/observer-stop-hook.mjs` on Stop event (Task B5), verified collision against 6-component economy/skill-discipline architecture:
+
+- **User-level** `~/.claude/settings.json` already has Stop hook: **agent-type** Sonnet-4.6 economy compliance verifier (analyzes transcript for claim-without-evidence violations).
+- **Project-level** `.claude/settings.json` — Stop slot empty.
+
+**Result**: no overwrite. observer-stop-hook will be added as **command-type entry in project-level Stop array**. Project + user scopes are independent slots in Claude Code 2.x — both run on the same Stop event without conflict. The agent verifier (user scope) and the JSONL appender (project scope) have non-overlapping responsibilities.