chore: remove existing directory warning from install.py

feat: add uninstall.py for clean plugin removal

refactor: consolidate install.sh and install.ps1 into a single install.py

fix: update CLAUDE.md and .claude/ references to AGENTS.md and .sisyphus/ in agent instructions

chore: add .opencode/ to .gitignore

chore: remove unnecessary .gitkeep files

refactor: rename .opencode to plugin-src to prevent auto-loading

fix: update the model to the latest version

feat: add plugins directory copy step to install scripts

feat: add shell.env plugin to inject CLAUDE_* env vars via OpenCode API

fix: add resource path notes to skills and fix CLAUDE_* env var resolution

docs: update README install section for global/local modes

fix: use hex color codes in agents, default install to global ~/.config/opencode

chore: remove tracked .sisyphus from git cache

docs: add hierarchical AGENTS.md for project navigation