refactor(oxlint/lsp): store Option<Vec<FixedContent>> for DiagnosticReport code action part

[Sysix]

This PR refactors the diagnostic code action data structure in the language server, replacing the PossibleFixContent enum with an Option design. This simplifies the code by using a more direct representation where None indicates no fixes and Some(LinterCodeAction) contains a vector of available fixes.

Because the fixes are mostly 2 or more, this data struct is better (that what ChatGPT told me).
2 for ignoring the diagnostic for the line/file and possible more for fixing it.
The only time a fix is zero or one is when a parser error happened or an unused disable directive is reported.

Given:
-mostly None
-often multiple fixes (≥3)
-rarely Single
→ You should prefer the Option<Vec> version.
✔️ Smaller memory use for the dominant cases
✔️ No enum tag overhead
✔️ Only one representation (Vec) simplifies code
✔️ Very efficient for multiple items
✔️ No downside since Single is rare

[Sysix]

• perf(lsp): avoid some clones, part 2 #16543
• perf(lsp): avoid some clones #16519
• perf(oxlint/lsp): store only LinterCodeAction instead of the complete DiagnosticReport #16516
• refactor(oxlint/lsp): prefill FixedContent.message and remove Option wrapper #16515
• refactor(oxlint/lsp): store Option<Vec<FixedContent>> for DiagnosticReport code action part #16514 👈 (View in Graphite)
• test(oxlint/lsp): add CodeAction.is_preferred info to snapshot files #16513
• main

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[Copilot]

Pull request overview

This PR refactors the diagnostic code action data structure in the language server, replacing the PossibleFixContent enum with an Option<LinterCodeAction> design. This simplifies the code by using a more direct representation where None indicates no fixes and Some(LinterCodeAction) contains a vector of available fixes.

Key changes:

• Replaced PossibleFixContent enum (None/Single/Multiple variants) with Option<LinterCodeAction> containing Vec<FixedContent>
• Refactored add_ignore_fixes to mutate a vector instead of returning a transformed enum
• Updated code action generation logic to work with the new structure using filter_map

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 10 comments.

File	Description
crates/oxc_language_server/src/linter/error_with_position.rs	Introduces LinterCodeAction struct, removes PossibleFixContent enum, and refactors message_to_lsp_diagnostic and add_ignore_fixes to use mutable vector approach
crates/oxc_language_server/src/linter/code_actions.rs	Updates function signatures to accept LinterCodeAction references and simplifies logic by working directly with vectors instead of enum matching
crates/oxc_language_server/src/linter/server_linter.rs	Adapts code action generation to use filter_map with the new Option<LinterCodeAction> structure

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[camc314]

Merge activity

• Dec 5, 1:46 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Dec 5, 1:46 PM UTC: camc314 added this pull request to the Graphite merge queue.
• Dec 5, 1:55 PM UTC: Merged by the Graphite merge queue.