DC-005: Fix all 138 broken test paths after src/ refactor

After the DC-005 module reorganization (41 files moved into src/ subdirs),
138 test suites failed because the refactor script's path-rewrite logic
missed three categories:

1. Files inside src/ doing 'require("./src/...")' — should be 'require("../...")'
2. Files in src/X/Y/ doing 'require("../../../src/...")' — should be 'require("../../...")'
3. Test files in __tests__/ with leftover 'require("../../../src/...")' paths

Root cause: the original refactor script ran before all files were moved,
so it computed relative paths against stale filesystem state.

Result:
- 30/30 test suites pass
- 879/879 tests pass (was: 18/30 suites, 614/687 tests)

Also fixed:
- routes/apps/restore.js: wrong responses import path
- routes/*/*.js: '../../src/utilities/X' → '../src/utilities/X' (depth 2 routes)

dashcaddy-api/__tests__/backup-manager.test.js

@@ -3,19 +3,19 @@
 
 jest.mock('fs');
 jest.mock('child_process');
-jest.mock('../credential-manager', () => ({
+jest.mock('../src/managers/credential-manager', () => ({
   exportBackup: jest.fn().mockReturnValue({ encrypted: 'cred-data' }),
   importBackup: jest.fn()
 }));
-jest.mock('../resource-monitor', () => ({
+jest.mock('../src/managers/resource-monitor', () => ({
   exportStats: jest.fn().mockReturnValue({ stats: [{ cpu: 10 }] }),
   importStats: jest.fn()
 }));
 
 const fs = require('fs');
 const crypto = require('crypto');
-const credentialManager = require('../credential-manager');
-const resourceMonitor = require('../resource-monitor');
+const credentialManager = require('../src/managers/credential-manager');
+const resourceMonitor = require('../src/managers/resource-monitor');
 
 // Setup defaults BEFORE requiring singleton (constructor calls loadConfig/loadHistory)
 fs.existsSync.mockReturnValue(false);
@@ -24,7 +24,7 @@ fs.writeFileSync.mockReturnValue(undefined);
 fs.mkdirSync.mockReturnValue(undefined);
 fs.unlinkSync.mockReturnValue(undefined);
 
-const backupManager = require('../backup-manager');
+const backupManager = require('../src/utilities/backup-manager');
 
 beforeEach(() => {
   jest.clearAllMocks();