feat(language_server): watch for fmt.configPath file content change

[Sysix]

The server now sends a request to the client, to watch for .oxfmtrc.json or custom configurable fmt.configPath file content changes.
The client will send a workspace/didChangeWatchedFiles notification to the server.

The client can also send workspace/didChangeConfiguration, for now the server will restart both tools.
This will be optimized by looking at which tool is responsible for the file in #14645

[Sysix]

• feat(editor): add off to oxc.lint.run configuration #14755
• refactor(language_server): move Diagnostics-map to WorkspaceWorker #14830
• feat(language_server): able to set off for run configuration #14746
• refactor(language_server): improve file watching for different tools #14645
• feat(editor): support oxc.fmt.configPath configuration #14639
• feat(language_server): watch for fmt.configPath file content change #14509 👈 (View in Graphite)
• test(language_server): add basic tests for WorkspaceWorker::did_change_configuration #14531
• main

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[Copilot]

Pull Request Overview

This PR adds file watcher support for the formatter configuration file, enabling the language server to detect and respond to changes in the formatter config file (similar to existing linter config watching).

Key changes:

• Added formatter config file watching when experimental formatter is enabled
• Refactored watcher management to handle multiple watchers (lint + format configs)
• Updated return types from single watcher to vector of watchers

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
crates/oxc_language_server/src/worker.rs	Added formatter config watcher logic in init_watchers and did_change_configuration; refactored return type to handle multiple watchers; added comprehensive test coverage
crates/oxc_language_server/src/backend.rs	Updated variable names and handling to work with vector of watchers instead of single watcher

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[Copilot]

Pull Request Overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

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[camc314]

Merge activity

• Oct 17, 10:59 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Oct 17, 10:59 AM UTC: camc314 added this pull request to the Graphite merge queue.
• Oct 17, 11:04 AM UTC: Merged by the Graphite merge queue.