Release 0.2.4: Hermes Desktop support and upgrade-safe companion

[CorsenAI]

Summary

• add first-class Hermes Desktop backend discovery while keeping CLI support
• move the local bridge to protocol 5 on loopback port 8767 with strict version validation
• make companion upgrades safe for both Desktop and CLI by isolating the broker from the replaceable virtual environment
• migrate validated local state from protocol 4 once and clean up exact legacy brokers only
• refresh installers, documentation, store copy, privacy disclosures, screenshots, and release evidence for 0.2.4

Validation

• 76 Python tests passed (6 platform-specific skips)
• 21 JavaScript tests passed
• packaged Chrome extension passed single-profile and multi-profile end-to-end tests
• exact 0.2.4 Chrome ZIP connected to a live Hermes Desktop 0.21.0 instance
• real Windows Desktop update completed, relaunched automatically, and the Connector process was not reported as an update blocker
• release artifacts are reproducible from a clean tree and recorded with SHA-256 hashes