Fix USB policy reporting and improve agent reliability

- Fix Zod schema to accept null values (nullable) for error/currentPolicy
- Add robust logging system writing to raven-agent.log file
- Rewrite auto-start using winreg with validation
- Auto-start agent on app setup if credentials exist
- Reduce retry attempts to 2 (1 + 1 retry after 2s)
- Replace provider's remote access on ID change (prevents duplicates)
- Update agent to v0.2.0

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/app/api/machines/usb-policy/route.ts

@@ -11,8 +11,8 @@ const getPolicySchema = z.object({
 const reportStatusSchema = z.object({
   machineToken: z.string().min(1),
   status: z.enum(["PENDING", "APPLYING", "APPLIED", "FAILED"]),
-  error: z.string().optional(),
-  currentPolicy: z.string().optional(),
+  error: z.string().nullable().optional(),
+  currentPolicy: z.string().nullable().optional(),
 })
 
 const CORS_METHODS = "GET, POST, OPTIONS"