Support hot-reload for plugins without session restart

Problem

Currently, plugins are only loaded at session startup. After installing a new plugin via /plugin install, users must restart their Claude Code session for the plugin to take effect. This creates friction, especially for:

• Testing plugins during development
• Installing plugins mid-session without losing context
• Quick iteration on hook configurations

Proposed Solution

Add the ability to reload plugins without restarting the session:

1. A /plugin reload command to refresh all plugins
2. Or automatic activation after /plugin install
3. Or a /hooks reload command to refresh hook configurations

Use Case

I created a notification plugin that plays a sound when Claude is waiting for input. After installing it, I had to restart my session to hear the notification - losing my conversation context.

Alternatives Considered

• Restarting the session (current workaround, loses context)
• Pre-installing plugins before starting work