Lock lease, 15 mins limit and new command

[0.1.1] - 2026-09-08

Added

• 15-minute minimum lock duration — shorter locks aren't reliably enforceable and are now rejected with a clear message.
• New lock lease mechanism (lease.rs) — a more robust handshake between extension and daemon for tracking active locks.
• mindgate profiles command for looking at current profiles

Known issues

• Linux session-lock (screen lock/suspend) can still intermittently cause the daemon to misjudge extension state. Fix in progress — do not treat this release as fully resolving that issue.