test(daemon): failing tests for slice 3.5 Codex feature flag (HG-5.1-5.4)

Per IMPL-PRD §5 + velocity-guard cadence boundary (d). 7 tests, all
currently FAIL (TDD red). Replaces activity-hook-injection-coupled
upsertCodexHooksFeature() being removed in next commit.

7 tests cover:
- HG-5.1: runtime.codex.hooks_enabled is in SETTINGS_VALID_KEYS
- HG-5.2: ensureCodexFeatureFlag(true) writes codex_hooks = true to
  ~/.codex/config.toml when file missing AND when file has prior content
  (preserves prior content)
- HG-5.3: idempotent (running twice doesn't duplicate); pre-existing
  [features] block with other flags is preserved when adding codex_hooks
- HG-5.4: ensureCodexFeatureFlag(false) does NOT touch ~/.codex/config.toml
  (file missing OR existing — user owns it)

Next commit:
- Add 'runtime.codex.hooks_enabled' to SETTINGS_VALID_KEYS + ENV_MAP +
  KEY_TO_PATH (and lockstep CLI ConfigStore)
- Add ensureCodexFeatureFlag(enabled: boolean) method on
  CodexRuntimeAdapter (reuses existing upsertCodexHooksFeature TOML
  helper that's about to move from coupled location)
- Wire into daemon startup

Per IMPL-PRD §5.x + plugin-primitive Phase 3a slice 3.5.

packages/daemon/test/codex-hooks-feature-flag.test.ts

@@ -0,0 +1,134 @@
+// Test suite for plugin-primitive Phase 3a slice 3.5 — Codex feature flag
+// (codex_hooks = true). Per IMPL-PRD §5 + velocity-guard cadence boundary
+// (d) 2026-05-10.
+//
+// Replaces the activity-hook-injection-coupled upsertCodexHooksFeature()
+// being removed in Phase 3a slice 3.1. New shape:
+//
+// 1. OpenRig setting `runtime.codex.hooks_enabled` (default true)
+// 2. CodexRuntimeAdapter exposes ensureCodexFeatureFlag(setting) that
+//    writes codex_hooks = true to ~/.codex/config.toml when setting=true
+// 3. Idempotent: running twice produces no duplication
+// 4. User override (setting=false) → daemon does NOT mutate Codex config
+
+import { describe, it, expect, vi } from "vitest";
+import { CodexRuntimeAdapter, type CodexAdapterFsOps } from "../src/adapters/codex-runtime-adapter.js";
+import { SETTINGS_VALID_KEYS } from "../src/domain/user-settings/settings-store.js";
+
+function mockTmux() {
+  return {
+    sessionExists: vi.fn().mockResolvedValue(true),
+    sendKeys: vi.fn().mockResolvedValue(undefined),
+    capturePaneContent: vi.fn().mockResolvedValue(""),
+    getPaneCommand: vi.fn().mockResolvedValue(""),
+    listSessions: vi.fn().mockResolvedValue([]),
+    runCommandInSession: vi.fn().mockResolvedValue({ stdout: "", stderr: "", exitCode: 0 }),
+    setEnvVar: vi.fn().mockResolvedValue(undefined),
+  } as unknown as ConstructorParameters<typeof CodexRuntimeAdapter>[0]["tmux"];
+}
+
+function mockCodexFs(files?: Record<string, string>): CodexAdapterFsOps & { _store: Record<string, string> } {
+  const store: Record<string, string> = { ...files };
+  return {
+    readFile: (p: string) => { if (p in store) return store[p]!; throw new Error(`Not found: ${p}`); },
+    writeFile: (p: string, c: string) => { store[p] = c; },
+    exists: (p: string) => p in store,
+    mkdirp: () => {},
+    listFiles: (dir: string) => Object.keys(store).filter((k) => k.startsWith(dir + "/")).map((k) => k.slice(dir.length + 1)),
+    homedir: "/home/test",
+    _store: store,
+  } as CodexAdapterFsOps & { _store: Record<string, string> };
+}
+
+describe("Slice 3.5 — Codex feature flag (runtime.codex.hooks_enabled)", () => {
+  // ============================================================
+  // HG-5.1: setting exists in canonical valid-keys lists
+  // ============================================================
+
+  it("HG-5.1 — runtime.codex.hooks_enabled is in SETTINGS_VALID_KEYS", () => {
+    expect(SETTINGS_VALID_KEYS as readonly string[]).toContain("runtime.codex.hooks_enabled");
+  });
+
+  // ============================================================
+  // HG-5.2: ensureCodexFeatureFlag writes codex_hooks = true
+  // ============================================================
+
+  it("HG-5.2 — ensureCodexFeatureFlag(true) writes codex_hooks = true to ~/.codex/config.toml when file missing", () => {
+    const fs = mockCodexFs(/* no existing file */);
+    const adapter = new CodexRuntimeAdapter({ tmux: mockTmux(), fsOps: fs });
+
+    adapter.ensureCodexFeatureFlag(true);
+
+    const written = fs._store["/home/test/.codex/config.toml"];
+    expect(written).toBeDefined();
+    expect(written).toContain("[features]");
+    expect(written).toContain("codex_hooks = true");
+  });
+
+  it("HG-5.2 — ensureCodexFeatureFlag(true) sets codex_hooks = true while preserving existing config content", () => {
+    const existing = `[model_provider]\nname = "openai"\n\n[other_section]\nfoo = "bar"\n`;
+    const fs = mockCodexFs({ "/home/test/.codex/config.toml": existing });
+    const adapter = new CodexRuntimeAdapter({ tmux: mockTmux(), fsOps: fs });
+
+    adapter.ensureCodexFeatureFlag(true);
+
+    const written = fs._store["/home/test/.codex/config.toml"]!;
+    expect(written).toContain('name = "openai"');
+    expect(written).toContain('foo = "bar"');
+    expect(written).toContain("[features]");
+    expect(written).toContain("codex_hooks = true");
+  });
+
+  // ============================================================
+  // HG-5.3: idempotent
+  // ============================================================
+
+  it("HG-5.3 — ensureCodexFeatureFlag(true) is idempotent (running twice doesn't duplicate codex_hooks)", () => {
+    const fs = mockCodexFs();
+    const adapter = new CodexRuntimeAdapter({ tmux: mockTmux(), fsOps: fs });
+
+    adapter.ensureCodexFeatureFlag(true);
+    adapter.ensureCodexFeatureFlag(true);
+
+    const written = fs._store["/home/test/.codex/config.toml"]!;
+    const matches = written.match(/codex_hooks = true/g) ?? [];
+    expect(matches).toHaveLength(1);
+    const featuresMatches = written.match(/\[features\]/g) ?? [];
+    expect(featuresMatches).toHaveLength(1);
+  });
+
+  it("HG-5.3 — pre-existing [features] block with other flags is preserved when adding codex_hooks", () => {
+    const existing = `[features]\nother_flag = false\n`;
+    const fs = mockCodexFs({ "/home/test/.codex/config.toml": existing });
+    const adapter = new CodexRuntimeAdapter({ tmux: mockTmux(), fsOps: fs });
+
+    adapter.ensureCodexFeatureFlag(true);
+
+    const written = fs._store["/home/test/.codex/config.toml"]!;
+    expect(written).toContain("other_flag = false");
+    expect(written).toContain("codex_hooks = true");
+  });
+
+  // ============================================================
+  // HG-5.4: user override (false) → daemon does not mutate
+  // ============================================================
+
+  it("HG-5.4 — ensureCodexFeatureFlag(false) does NOT touch ~/.codex/config.toml when file missing", () => {
+    const fs = mockCodexFs();
+    const adapter = new CodexRuntimeAdapter({ tmux: mockTmux(), fsOps: fs });
+
+    adapter.ensureCodexFeatureFlag(false);
+
+    expect(fs._store["/home/test/.codex/config.toml"]).toBeUndefined();
+  });
+
+  it("HG-5.4 — ensureCodexFeatureFlag(false) does NOT touch existing ~/.codex/config.toml content (user owns it)", () => {
+    const existing = `[features]\ncodex_hooks = false\nother = true\n`;
+    const fs = mockCodexFs({ "/home/test/.codex/config.toml": existing });
+    const adapter = new CodexRuntimeAdapter({ tmux: mockTmux(), fsOps: fs });
+
+    adapter.ensureCodexFeatureFlag(false);
+
+    expect(fs._store["/home/test/.codex/config.toml"]).toBe(existing);
+  });
+});