fix(cache): use user-writable ~/.serve.zone/dcrouter for TsmDB and centralize data path logic

readme.hints.md

@@ -46,7 +46,7 @@ Source at `../../push.rocks/smartmta`, release with `gitzone commit -ypbrt`
 ### SmartProxy v23.1.2 Route Validation
 - SmartProxy 23.1.2 enforces stricter route validation
 - Forward actions MUST use `targets` (array) instead of `target` (singular)
-- Test configurations that call `DcRouter.start()` need `cacheConfig: { enabled: false }` to avoid `/etc/dcrouter` permission errors
+- Test configurations that call `DcRouter.start()` need `cacheConfig: { enabled: false }` to avoid starting a real MongoDB process in tests
 
 ```typescript
 // WRONG - will fail validation
@@ -693,7 +693,7 @@ The configuration UI has been converted from an editable interface to a read-onl
 ## Smartdata Cache System (2026-02-03)
 
 ### Overview
-DcRouter now uses smartdata + LocalTsmDb for persistent caching. Data is stored at `/etc/dcrouter/tsmdb`.
+DcRouter now uses smartdata + LocalTsmDb for persistent caching. Data is stored at `~/.serve.zone/dcrouter/tsmdb`.
 
 ### Technology Stack
 | Layer | Package | Purpose |
@@ -747,7 +747,7 @@ await email.delete();
 const dcRouter = new DcRouter({
   cacheConfig: {
     enabled: true,
-    storagePath: '/etc/dcrouter/tsmdb',
+    storagePath: '~/.serve.zone/dcrouter/tsmdb',
     dbName: 'dcrouter',
     cleanupIntervalHours: 1,
     ttlConfig: {