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/shared/migrate-legacy-plugin-entry.test.ts

@@ -1,6 +1,6 @@
 /// <reference path="../../bun-test.d.ts" />
 
-import { afterEach, beforeEach, describe, expect, it, mock } from "bun:test"
+import { afterAll, afterEach, beforeEach, describe, expect, it, mock } from "bun:test"
 import { mkdirSync, readFileSync, rmSync, writeFileSync } from "node:fs"
 import { tmpdir } from "node:os"
 import { join } from "node:path"
@@ -9,6 +9,10 @@ async function importFreshMigrationModule(): Promise<typeof import("./migrate-le
   return import(`./migrate-legacy-plugin-entry?test=${Date.now()}-${Math.random()}`)
 }
 
+afterAll(() => {
+  mock.restore()
+})
+
 describe("migrateLegacyPluginEntry", () => {
   let testDir = ""