Scope moved sessions to resolved locations

[eivindjonassen]

Summary

• Keep transcript, composer, completion, file-search, form, and execution queries disabled until session metadata resolves the authoritative location.
• Migrate the open session cache to that location and use it for messages, mutations, child navigation, workspace reconciliation, and Diff.
• Add regression coverage for a session whose route location is stale after a move.

Verification

• pnpm check
• 293 mobile tests
• iOS and Android Hermes exports
• git diff --check