fix(linter): skip running tsgolint when no files need type aware linting

[Copilot]

When using oxlint --type-aware with only non-TypeScript files (e.g., Svelte, Vue, or other files), tsgolint would fail with the error:

Error running tsgolint: "exit status: exit status: 1, error: no files specified in config"

This occurred because the json_input method filters files to only include those with valid JavaScript/TypeScript extensions, but the code didn't check if the filtered result was empty before attempting to run tsgolint.

The fix adds an early return in TsGoLintState::lint() when no TypeScript/JavaScript files remain after filtering, similar to the existing check for empty input paths. This ensures tsgolint is only invoked when there are actual TypeScript files to process.

Example scenarios that now work:

# Only Svelte files - no longer crashes
oxlint --type-aware component.svelte

# Mixed TypeScript and Svelte files - both processed correctly  
oxlint --type-aware component.svelte helper.ts

# Only TypeScript files - continues to work as before
oxlint --type-aware helper.ts

Added test case test_tsgolint_no_typescript_files to verify the fix and prevent regression.

Fixes #13501.

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[graphite-app]

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[Copilot]

Pull Request Overview

Fixes a crash in tsgolint when running oxlint --type-aware with only non-TypeScript files (e.g., Svelte, Vue). The issue occurred because tsgolint would attempt to run even when no TypeScript/JavaScript files remained after filtering, resulting in a "no files specified in config" error.

• Adds early return in TsGoLintState::lint() when no TypeScript/JavaScript files are found after filtering
• Includes test case to verify the fix with a Svelte file containing linting violations
• Ensures tsgolint is only invoked when there are actual TypeScript files to process

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
crates/oxc_linter/src/tsgolint.rs	Adds early return check to prevent tsgolint execution when no TypeScript files remain
apps/oxlint/src/lint.rs	Adds test case to verify tsgolint doesn't crash with non-TypeScript files
apps/oxlint/fixtures/tsgolint/test.svelte	Test fixture containing Svelte code with a debugger statement
apps/oxlint/src/snapshots/fixtures__tsgolint_--type-aware test.svelte@oxlint.snap	Expected test output showing regular linting still works

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #13502 will not alter performance

_{Comparing copilot/fix-13501 (24b0fd8) with main (b677376)}

Summary

✅ 37 untouched benchmarks