* Replace hardcoded custom modes filename with GlobalFileNames constant
* Remove 'cline' prefix from mcpSettings filename
* Use GlobalFileNames.customModes in modes.ts
* replace two more `cline_mcp_settings` with `mcp_settings` in tests.
* feat: add settings file migration for new file naming convention
- Implement migrateSettings function to rename legacy settings files to new format
- Migrate cline_custom_modes.json to new custom modes filename
- Migrate cline_mcp_settings.json to new MCP settings filename
- Add TODO to remove migration code in September 2025 (6 months after implementation)
- Make activate function async to support migration on startup
* Add associated changeset
* removed unused import
* refactor: move migrateSettings to dedicated utility file
- Extract migrateSettings function from extension.ts to src/utils/migrateSettings.ts
- Update extension.ts to import and use the extracted function
- Update tests to use the real implementation
- Improve dependency injection by passing outputChannel as parameter
- Enhance maintainability by isolating temporary migration code (to be removed Sept 2025)
* Update src/extension.ts
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Co-authored-by: Matt Rubens <mrubens@users.noreply.github.com>
