feat(release): self-determination - ensure at launch, drift warnings, M20 packages/* decision (#38)

- release.sh ensure: aligned no-op; drift -> package-if-needed + health-gated
  activate (M3 gate-then-flip, automated)
- ensure_release_aligned in common.sh: invoked by hello/verify/agent;
  MOSAIC_ENSURE_SKIP guards recursion; run-task warns on drift without
  auto-aligning (workers/suites never trigger builds or model gates)
- ROADMAP: M20 decision recorded - v2 adopts packages/* monorepo at usurpation
- BUILD-LOG Phase 20 + tool-race process note

Live-verified: post-reset pointer loss auto-restored via health-gated
ensure; drift warning fires on desired-version bump; idempotent no-op on
aligned state.

Closes #38

BUILD-LOG.md

@@ -401,3 +401,29 @@ left them unwritten at the time of work. Ground truth for each entry: the git
 history (commit subjects/bodies), the Gitea milestone/issue records (#32, #34,
 #35, #36), and the suite files themselves. No facts were reconstructed from
 memory alone.
+
+---
+
+## Phase 20: Release self-determination (M16)
+
+### Entry 20.1 — before
+
+- Timestamp: 2026-09-03
+- Intended action: The system determines what is installed and aligns itself; the user never manually runs release.sh. `release.sh ensure` (align-or-noop) invoked automatically by human-facing launchers (hello, verify, agent); run-task reports drift without auto-aligning (workers/suites must not trigger builds or model gates mid-automation).
+- Reason: Owner direction — intelligence in operation; post-reset pointer loss required a manual release command, which contradicts the self-healing design.
+- Expected result: post-reset pointer loss auto-restores via health-gated ensure; drift warns on run-task; aligned state is a no-op; M20 packages/* decision recorded.
+
+### Entry 20.2 — after
+
+- Timestamp: 2026-09-03
+- Commands run: ensure with pointer removed (live drift); ensure idempotence; drift-warning demo via RELEASE bump without packaging; full suites.
+- Observed result: drift detected (active: none, desired: 0.0.11) -> health-gated activate -> aligned; second ensure no-op; run-task drift warning fired on desired-version bump without packaging; all suites green (24/68/17/14 + verify).
+- Failure or correction:
+  1. First run-task edit anchor missed (inline comment mismatch) — reapplied with exact text.
+  2. RELEASE was temporarily bumped to 0.0.12 without packaging for the drift demo — restored to 0.0.11; state pointer remained aligned.
+- M20 decision recorded in ROADMAP.md: v2 adopts packages/* monorepo structure at usurpation (owner, continuity-first).
+- Process note (tool races): mechanism confirmed — batching a file write/edit and a dependent bash command in one parallel block runs the bash before the write flushes. Consequences: lost doc updates, stale anchors, one premature grep. Operating rule: dependent calls sequential; every write verified before claimed complete.
+
+## Result (M16)
+
+Release self-determination live: the system aligns itself to RELEASE without manual commands. Suites 24/68/17/14 + verify green.