PR Checklist

Closes #

What is the new behavior?

Adds a project-specific angular-version-support skill under .agents/skills and exposes it through .claude/skills with a relative symlink. The skill documents the deterministic Angular compatibility update workflow for this repo, adds OpenAI skill metadata, and includes a Node 22-compatible TypeScript helper for updating Angular peer ranges and the compatibility matrix without a runner.

Does this PR introduce a breaking change?

• Yes
• No

Other information

Validation performed:

• node --check .agents/skills/angular-version-support/scripts/add-angular-version.ts
• Fixture update for Angular 20, including idempotent second run
• Real repo --dry-run with no tracked file changes
• Skill metadata/frontmatter checks
• node --test tools/angular-compat/*.test.mjs
• pnpm run compat:assert
• pnpm run compat:matrix
• git diff --check

Forward-tested the skill with a worker agent using the prompt to add Angular 20 support. That test validated the expected deterministic files and led to tightening the helper to backfill missing stable floor/latest rows.

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