Auto-sync cron: run know sync every 15 min on all machines

[jordanpartridge]

Problem

Knowledge entries created on one machine don't propagate to others until manual know sync. Sessions on Mac and Odin are isolated.

Solution

Add a cron hook that runs know sync every 15 minutes on each machine. Include in plugin install script.

Acceptance Criteria

• Cron entry added: */15 * * * * know sync
• Plugin install.sh sets up the cron automatically
• Verify entries created on Mac appear on Odin within 15 min

Part of v1.1.0 release.