Installed plugin not enabled - hooks never loaded

Environment

• Claude Code version: 2.0.70
• OS: macOS (Darwin 25.1.0)
• API: AWS Bedrock (CLAUDE_CODE_USE_BEDROCK=1)

Bug Description

A plugin is correctly installed and recognized in installed_plugins.json, but it's never enabled. As a result, the plugin's hooks are never loaded.

Debug Log Evidence

Loaded 1 installed plugins from /Users/.../.claude/plugins/installed_plugins.json
Initialized versioned plugins system with 1 plugins
Found 0 plugins (0 enabled, 0 disabled)  ← BUG: Should be 1 enabled
Registered 0 hooks from 0 plugins

The plugin is loaded into the "versioned plugins system" but shows as "0 enabled, 0 disabled" - it's in a limbo state where it exists but isn't active.

Steps to Reproduce

1. Add a marketplace: /plugin marketplace add thedotmack/claude-mem
2. Install the plugin: /plugin install claude-mem
3. Restart Claude Code
4. Check debug log: cat ~/.claude/debug/latest | grep -i plugin
5. Observe: "Found 0 plugins (0 enabled, 0 disabled)" despite 1 being installed

Expected Behavior

• Plugin should show as "1 enabled"
• Plugin's hooks (from hooks/hooks.json) should be registered
• Hooks should fire on events like PostToolUse, SessionStart, etc.

Actual Behavior

• Plugin shows in installed_plugins.json with correct path and version
• Plugin's hooks/hooks.json exists with valid configuration
• But plugin is never "enabled"
• "Registered 0 hooks from 0 plugins"
• Hooks never fire

Additional Context

• The plugin briefly worked after initial installation
• After an auto-update (7.2.4 → 9.0.0), hooks stopped loading entirely
• Manually adding hooks to ~/.claude/settings.json also shows "Found 0 hook matchers in settings"
• This may be related to Bedrock mode, but unclear

Files

installed_plugins.json:

{
  "version": 2,
  "plugins": {
    "claude-mem@thedotmack": [
      {
        "scope": "user",
        "installPath": "/Users/.../.claude/plugins/cache/thedotmack/claude-mem/9.0.0",
        "version": "9.0.0",
        "installedAt": "2025-12-16T20:19:28.246Z",
        "lastUpdated": "2026-01-06T04:10:42.570Z",
        "isLocal": true
      }
    ]
  }
}

Plugin's hooks/hooks.json exists with valid SessionStart, PostToolUse, Stop hooks configured.