feat: add pre-commit sensitive file blocker and support request issue template
Completes issue #7 (public mirror setup):
- .githooks/pre-commit: blocks sensitive filenames (.env, *.key, *.pem,
id_rsa, credentials.json, etc.) and credential content patterns (private
key headers, AWS keys, GitHub tokens, Stripe secret keys, generic API
key assignments) from being committed
- .github/ISSUE_TEMPLATE/support_request.md: third issue template for
usage questions alongside existing bug report and feature request
pyr0ball
ed175e9fb4