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  (unused, superseded by paginateVersions) and unused exception classes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.

app/utils/schedule_window.ts

@@ -1,4 +1,4 @@
-import type { ScheduleWindow } from '../domain/configuration/configuration.js'
+import type { ScheduleWindow } from '#domain/configuration/configuration'
 
 /**
  * Checks if the current time (or provided time) falls within the schedule window.
@@ -41,10 +41,7 @@ export function isWithinSchedule(schedule: ScheduleWindow | undefined, now?: Dat
 /**
  * Gets the local hour and day-of-week for a given Date in a specific IANA timezone.
  */
-function getLocalTimeParts(
-  date: Date,
-  timezone: string
-): { hour: number; dayOfWeek: number } {
+function getLocalTimeParts(date: Date, timezone: string): { hour: number; dayOfWeek: number } {
   const formatter = new Intl.DateTimeFormat('en-US', {
     timeZone: timezone,
     hour: 'numeric',