feat(parser): add syntax errors for constructor declarations

[Boshen]

Summary

• Add TS1031 error for declare modifier on constructor: declare constructor() {}
• Add TS1093 error for return type annotation on constructor: constructor(): number {}

Test plan

• Parser conformance tests updated
• Negative Passed: 1498 → 1500 (+2 tests)

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR adds two TypeScript syntax error checks for invalid constructor declarations: TS1031 for the declare modifier on constructors and TS1093 for return type annotations on constructors.

Changes:

• Added validation to reject declare modifier on constructor declarations (TS1031)
• Added validation to reject return type annotations on constructor declarations (TS1093)

Reviewed changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 1 comment.

File	Description
tasks/coverage/snapshots/parser_typescript.snap	Updated test results showing 2 additional negative tests now passing (parserConstructorDeclaration4.ts and parserConstructorDeclaration10.ts)
crates/oxc_parser/src/js/class.rs	Added error check for declare modifier in parse_constructor_declaration and error check for return type in check_method_definition_constructor
crates/oxc_parser/src/diagnostics.rs	Added two new diagnostic functions: declare_constructor (TS1031) and constructor_return_type (TS1093)

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[codspeed-hq]

CodSpeed Performance Report

Merging this PR will not alter performance

_{Comparing feat/parser-constructor-errors (8442de9) with main (a95b9bb)¹}

Summary

✅ 42 untouched benchmarks
⏩ 3 skipped benchmarks²

Footnotes

1. No successful run was found on main (312da18) during the generation of this report, so a95b9bb was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

2. 3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[Boshen]

Merge activity

• Jan 19, 8:33 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Jan 19, 8:40 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Jan 19, 8:46 AM UTC: Merged by the Graphite merge queue.