Add the PR review config and fix the memory gate (0.2.1)

[Yanir-R]

What and why

• Adds .pr_agent.toml: lean settings for an automatic PR review (review and improve only, at most 5 findings) with a short checklist for a Claude Code mod: capabilities, hooks, the $ rules, in-memory data and its reset, privacy, output proof, compatibility, tests, release.
• Fixes a bug in the memory-only gate in scripts/release-check.sh. The first version of its pattern check returned the wrong exit status and would have passed a mod that calls the store. A planted $.store.set now makes the gate fail. The capability names are no longer written out in one pattern, so a plain text scan does not read them as calls.
• Lists the classic.SessionStart reset hook in the README.
• Version 0.2.1.

Checklist

• claude plugin validate . and claude plugin test . pass.
• bash scripts/scan.sh passes.
• A new rule has a test, and I checked that the test fails when the code is wrong. (The gate was checked with a planted store call.)
• I added a line under the changelog.
• The tests and examples use made-up data. Nothing comes from a real session.
• I added no network access and no file access.
• I did not rename the command, a setting or the plugin name.