refactor: remove unused hide_missing_ids functionality

- Remove hide_missing_ids parameter from all database functions
- Remove hide_missing_ids from API routes and query parameters
- Remove hide_missing_ids filtering logic from SQLite queries
- Update all tests to remove hide_missing_ids assertions
- Clean up codebase since internalTransactionId extraction is now fixed

This functionality was added as a workaround for missing internalTransactionId
values, but we've now fixed the root cause by properly extracting transaction
IDs from raw data during sync, making this workaround unnecessary.

frontend/package.json

@@ -4,7 +4,7 @@
   "version": "0.0.0",
   "type": "module",
   "scripts": {
-    "dev": "vite",
+    "dev": "VITE_API_URL=http://localhost:8000/api/v1 vite",
     "build": "tsc -b && vite build",
     "lint": "eslint .",
     "preview": "vite preview"