docs: use uv instead of pip in error messages

docs: use uv instead of pip for desloppify install

docs: clarify plugin vs hook, remove npx, improve agent prompt

fix duplicate ine in readme

docs: fix empty code block in AI agent prompt section

chore: add .gitignore, remove node_modules from tracking

rename: pushguard -> opencode-pushguard

docs: simplify zero-shot prompt to focus on pushguard only

Initial commit: pushguard - git pre-push quality gate