Cleanup GUI context injection for NlsService #2589

Task summary

In PR #2548, NlsService was changed to support an injected IdeContext so that NlsServiceTest can run in an isolated environment without being influenced by the IDE_OPTIONS environment variable.

However, when NlsService is created by the GUI without an injected context, it still lazily creates an IdeContextConsole in createUserEnvironmentVariables(). This was identified during review as an existing architectural hack that should be fixed.

Refactor the GUI integration so that NlsService always receives an appropriate IdeContext through dependency injection. Once all GUI call sites have been updated, remove the fallback lazy creation of IdeContextConsole from NlsService.

Acceptance criteria:

• GUI call sites create or provide the appropriate IdeContext when constructing NlsService.
• NlsService no longer needs a fallback IdeContextConsole when no context is injected.
• Existing locale handling and IDE_OPTIONS isolation behavior remain unchanged.
• Relevant unit and GUI tests continue to pass.

Additional context

Related pull request: #2548

The review discussion identifying this cleanup is available at #2548 (comment).

Relevant code:

• NlsService.java