v0.9.51

Changelog

• e5c27ef tests: Record the v0.9.50 launcher pin
• d3a5bda webui: Fix page header height
• 0c2ce08 docs: Require local encryption configuration before serving
• f9ac900 docs: Keep claim reads in request-time gates
• 1002f7e srv: Validate encryption configuration before serving
• 8f2ca8c srv: Shorten the missing encryption key error
• 1a79c31 docs: Preserve destination chrome throughout startup
• 64c9048 webui: Preserve page chrome while startup and data reads settle

Release notes

• Page titles keep a consistent vertical position, including System's navigation tabs.
• Loading pages retain their panels, columns, and disabled controls instead of flashing
  a loading label; repository manifest loading also retains its source panel.
• Page requests wait for startup and sign-in checks, preventing a temporary sign-in
  screen while an existing session loads.
• Server startup reports srv: SECRET is required immediately when the encryption key
  is missing, including on an unclaimed installation, and no longer waits for database
  access before starting HTTP service.

🤖 Drafted by Codex on chakrit's behalf.