fix(ci): simplify test runner to plain bun test by fixing mock.module() leakage

- Add afterAll(() => { mock.restore() }) to 52 test files missing cleanup
- Rewrite create-tool-guard-hooks.test.ts to use spyOn instead of barrel mock
- Fix skill-mcp-manager OAuth tests with missing mockTokens/mockLogin definitions
- Fix start-work hook: show worktree active block on resume with existing worktree_path
- Extract createWorktreeActiveBlock to worktree-block.ts to avoid circular import
- Replace 80-line isolated test runner CI config with single `bun test` command

src/features/tmux-subagent/manager.test.ts

@@ -1,4 +1,4 @@
-import { describe, test, expect, mock, beforeEach, spyOn } from 'bun:test'
+import { describe, test, expect, mock, beforeEach, spyOn, afterAll } from 'bun:test'
 import type { TmuxConfig } from '../../config/schema'
 import type { WindowState, PaneAction } from './types'
 import type { ActionResult, ExecuteContext } from './action-executor'
@@ -77,6 +77,8 @@ mock.module('./pane-state-querier', () => ({
       : null,
 }))
 
+afterAll(() => { mock.restore() })
+
 mock.module('./action-executor', () => ({
   executeActions: mockExecuteActions,
   executeAction: mockExecuteAction,