chore: add skills sync workflow

[felipefreitag]

We're going to distribute resend-skills from a single centralized repo that will behave as their "production"/"deployed" version.

To do that, each source repository (resend-cli, email-best-practices, react email) needs to push its skill changes to the resend-skills repo.

The skills must remain in their original repos for other forms of distribution, e.g., via npm.

[cubic-dev-ai]

2 issues found across 1 file

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name=".github/workflows/sync-skills.yml">

<violation number="1" location=".github/workflows/sync-skills.yml:47">
P1: Deletion-only changes inside a skill are not detected, so removed files/directories can remain stale in `resend-skills`.</violation>

<violation number="2" location=".github/workflows/sync-skills.yml:67">
P1: Whole-skill deletions are never synced because the workflow only processes source skill directories.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}