Merge remote-tracking branch 'origin/master' into codex/pr48-repo-hardening-rfcs

# Conflicts:
#	docs/adr/README.md
#	docs/rfc/009-session-persistence-and-resumability.md
#	docs/rfc/README.md
#	docs/rfc/implemented/2026-06-11-doc-sync-enforcement.md
#	docs/rfc/proposed/2026-06-14-acp-agent-client-protocol.md
#	examples/acp-agent/tests/acp.e2e.ts
#	packages/acp/README.md
#	packages/acp/src/index.ts
#	packages/acp/tests/stream-update.spec.ts
#	packages/agent-loop/src/loop.ts
#	packages/tools/src/index.ts

packages/session/tests/properties.spec.ts

@@ -1,5 +1,5 @@
 /**
- * Property-based tests for the Session event log (RFC 001 → ADR 0013).
+ * Property-based tests for the Session event log (the property-testing RFC).
  *
  * Generates arbitrary event logs and asserts the derivation invariants the
  * agent loop and replay depend on: deriveMessages is deterministic and

packages/session/tests/repair.spec.ts

@@ -82,6 +82,21 @@ describe('interruptedTurnClosers', () => {
     expect(closers.map(e => e.type)).toEqual(['step/end', 'turn/end'])
   })
 
+  it('does NOT synthesize a result after the owning step already closed', () => {
+    const events: SessionEvent[] = [
+      userTurnStart(2, 0),
+      { type: 'step/start', seq: 1, time: 1, data: { turn: 2, step: 1 } },
+      { type: 'assistant/message', seq: 2, time: 2, data: { turn: 2, step: 1, content: [
+        { type: 'tool-call', id: CallId('call-1'), name: 'bash', arguments: '{}' },
+      ] } },
+      { type: 'step/end', seq: 3, time: 3, data: { turn: 2, step: 1 } },
+    ]
+
+    const closers = interruptedTurnClosers(events)
+    expect(closers.map(e => e.type)).toEqual(['turn/end'])
+    expect(closers[0]?.seq).toBe(4)
+  })
+
   it('synthesizes results only for the still-open turn, not a committed earlier turn', () => {
     // Turn 1 completed with its own tool call+result (balanced). Turn 2 crashed
     // with an unanswered call. Only turn 2's call must get a synthetic result.