refactor: migrate all internal imports to package.json subpath aliases

- Add #domain, #protocol, #utils aliases to package.json imports map
- Replace all relative imports (./, ../, ../..) in app/ and
  database/mongo_migrations/ with the corresponding #alias imports,
  eliminating relative path traversal across the codebase
- Remove dead code: ConfigurationVersionModel.findByConfigurationIdentifier
  (unused, superseded by paginateVersions) and unused exception classes
  (NotFoundException, UnprocessableEntityException, DatabaseException)
  from app/exceptions/index.ts, keeping only BadRequestException
- Fix pre-existing syntax error in configuration_version.ts (mismatched
  parenthesis) that broke tsc
- Fix eqeqeq violation in configuration_service.ts and isNaN ->
  Number.isNaN in configuration_engine.ts / cwmp-1-0.ts / exchange_controller.ts
- Fix no-shadow violation in cwmp-1-0.ts EventStruct constructor
- Prettier formatting pass on touched files

Validated: tsc --noEmit clean, eslint app/ clean, full test suite green.

package.json

@@ -41,7 +41,10 @@
     "#database/*": "./database/*.js",
     "#tests/*": "./tests/*.js",
     "#start/*": "./start/*.js",
-    "#config/*": "./config/*.js"
+    "#config/*": "./config/*.js",
+    "#domain/*": "./app/domain/*.js",
+    "#protocol/*": "./app/protocol/*.js",
+    "#utils/*": "./app/utils/*.js"
   },
   "devDependencies": {
     "@adonisjs/assembler": "^8.4.0",