feat(state): add programmatic gates for STATE.md consistency (#1647)

* feat(state): add programmatic gates for STATE.md consistency

Adds four enforcement gates to prevent STATE.md drift:
- `state validate`: detects drift between STATE.md and filesystem
- `state sync`: reconstructs STATE.md from actual project state
- `state planned-phase`: records state after plan-phase completes
- Performance Metrics update in `phase complete`

Also fixes ghost `state update-position` command reference in
execute-phase.md (command didn't exist in CLI dispatcher).

Closes #1627

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

* fix(state): By Phase table regex ate next section when table body was empty

The lazy [\s\S]*? with a $ lookahead in byPhaseTablePattern would
match past blank lines and capture the next ## section header as table
body when no data rows existed. Replaced with a precise row-matching
pattern ((?:[ \t]*\|[^\n]*\n)*) that only captures pipe-delimited
lines. Added regression assertion to verify row placement.

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

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

tests/execute-phase-worktree-artifacts.test.cjs

@@ -85,18 +85,11 @@ describe('execute-phase worktree: shared artifact ownership (#1571)', () => {
     );
   });
 
-  test('post-wave orchestrator runs state update-position after completing a wave in worktree mode', () => {
+  test('ghost state update-position command removed from post-wave section (#1627)', () => {
     const content = fs.readFileSync(WORKFLOW_PATH, 'utf-8');
     assert.ok(
-      content.includes('state update-position'),
-      'post-wave section should contain orchestrator-owned state update-position command'
-    );
-    // Confirm it appears after the worktree agent block
-    const stateUpdateIdx = content.lastIndexOf('state update-position');
-    const worktreeAgentEnd = content.indexOf('**Sequential mode**');
-    assert.ok(
-      stateUpdateIdx > worktreeAgentEnd,
-      'state update-position must appear after the worktree agent block (orchestrator-owned, post-wave)'
+      !content.includes('state update-position'),
+      'state update-position was a ghost reference (command never existed in CLI dispatcher) — should be removed'
     );
   });