feat(app): Add WebStorm editor target

[ipanasenko]

A lot of my colleagues still use WebStorm, so I thought would be nice to support it too 🙏

This PR also loosens editor id check, to make client more independent from server in terms of supported editors.
WebStorm is gated for app version >0.1.50, but it can be removed when enough users upgrade.

Summary

• add WebStorm to the available editor targets and bundled editor icons
• keep flexible editor ids in shared message types while filtering legacy clients to the legacy-safe editor subset
• extend workspace/editor tests for WebStorm and unknown editor ids