feat: add claude_plugin_adapter

[Jiaq1Zhu]

feat: adapter to install and wire Claude Code-style plugins

Closes #471

Overview

This PR implements a first-class plugin adapter (claude_plugin_adapter) that allows Code Puppy to dynamically consume and wire Claude Code-style plugins. It supports the installation, uninstallation, and synchronization of Skills, MCP Servers, Agent profiles, and Hook configurations without requiring a system restart.

Changes Made

• Skills Adapter (adapters/skills.py): Detects skills/ directories inside Claude plugins and dynamically adds/removes them from Code Puppy's skill system using add_skill_directory/remove_skill_directory.
• MCP Server Adapter (adapters/mcp.py): Synchronizes a plugin's .mcp.json into the user's mcp_servers.json. We enforce idempotency using a "_managed_by" tag.
• Agents Adapter (adapters/agents.py): Extracts metadata from markdown agent files using YAML frontmatter parsing. The adapter maps tool names via the resolve_internal_name() system and writes the synchronized agents to the user's agents/ directory (again, tracked via _managed_by).
• Hooks Engine Integration (claude_code_hooks/config.py): Enhances hook configurations by recursively expanding ${CLAUDE_PLUGIN_ROOT} and $CLAUDE_PLUGIN_ROOT to the local plugin directory (~/.code_puppy/claude_plugins/).
• Hot-Reloading & Resync (installer.py, register_callbacks.py):
  • Exposes two new custom commands: /plugin install <path> and /plugin uninstall <name>.
  • Wires up the startup callback to re-sync all installed plugins dynamically on boot.
  • Adds an agent_reload hook inside claude_code_hooks/register_callbacks.py to allow the Hook Engine to re-initialize gracefully during live uninstalls.

Testing

• Automated Tests: Added complete unit tests for all components in tests/plugins/claude_plugin_adapter/.
• Manual Verification: Created a mock superpowers plugin and verified end-to-end functionality of /plugin install and /plugin uninstall across skills, agents, MCP configurations, and hook environments.
• Real-World Verification: Successfully tested the adapter using the third-party claude-mem plugin. Verified that:
  • The plugin's .mcp.json automatically injected the mcp-search server configuration into Code Puppy's mcp_servers.json (tracked safely with the _managed_by tag):

    {
      "mcp_servers": {
        "mcp-search": {
          "type": "stdio",
          "command": "node",
          "args": [ "-e", "..." ],
          "_managed_by": "claude_plugin_adapter:plugin"
        }
      }
    }

  • The plugin's skills/ directory was correctly discovered and recursively bound into Code Puppy's skill context, expanding the agent's capabilities dynamically:

    >>> get_skill_directories()
    ['/Users/xx/.code_puppy/skills', '/Users/xx/Dev/code_puppy/.code_puppy/skills', '/Users/xx/Dev/code_puppy/skills', '/Users/xx/.code_puppy/claude_plugins/plugin/skills']

[Jiaq1Zhu]

@mpfaffenberger, found this very interesting feature while browsing the issue list. Adapting the Claude Code plugin sounds like a good way to improve eco system indeed. Tested it with a couple of mock plugins and added an uninstall function. Can you please review this while you got sometime.

[thomwebb]

Heads up — plugins have been moved out of this repo into a dedicated repository: https://github.com/mpfaffenberger/code_puppy_core_plugins. This PR touches code under code_puppy/plugins/, so it'll likely need to be rebased/reworked against the new plugins repo rather than code_puppy core. Thanks for the contribution!

[thomwebb]

Closing this PR since every file it touches lives under code_puppy/plugins/ or tests/plugins/, and plugins have been moved out of this repo into a dedicated one: https://github.com/mpfaffenberger/code_puppy_core_plugins

Feel free to reopen this PR (or open a fresh one) against the new plugins repo -- the change itself looks good, it just needs a new home. Thanks for the contribution!