feat: add permanent whitelist list endpoint and rename DB table

- Add GET /api/whitelist/perm/list to list permanent whitelisted entries
- Implement permWhitelistListHandler with API key verification
- Rename permanent_whitelist table to perm_whitelist for consistency
- Update default DB path from ./data to /data
- Comment out build job in CI/CD workflow

docs/api.md

@@ -80,6 +80,23 @@ curl -X POST http://127.0.0.1:8080/api/whitelist/perm \
   -d '{"entry":"203.0.113.10"}'
 ```
 
+### GET /api/whitelist/perm/list
+
+List all currently active permanent whitelisted IPs.
+
+**Authorization:** Bearer `{API_TOKEN}`
+
+**Response body:**
+
+```json
+[
+  {
+    "ip": "1.2.3.4",
+    "reason": "my laptop",
+  }
+]
+```
+
 ### DELETE /api/whitelist/perm/{entry}
 
 Remove a permanent whitelisted IP or CIDR range.