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/hooks/directory-readme-injector/injector.test.ts

@@ -1,4 +1,4 @@
-import { afterEach, beforeEach, describe, expect, it, mock } from "bun:test"
+import { afterAll, afterEach, beforeEach, describe, expect, it, mock } from "bun:test"
 import { randomUUID } from "node:crypto"
 import { mkdirSync, rmSync, writeFileSync } from "node:fs"
 import { tmpdir } from "node:os"
@@ -15,6 +15,10 @@ mock.module("./storage", () => ({
   },
 }))
 
+afterAll(() => {
+  mock.restore()
+})
+
 function createPluginContext(directory: string): PluginInput {
   return { directory } as PluginInput
 }