fix(app): truncate compact composer model label

[dsingal0]

Summary

• keep the compact composer controls on one row
• truncate the compact model trigger label before it can collide with the mic/send controls
• add a compact-only width cap so Android narrow layouts preserve the action buttons

Testing

• npm run format
• npm run build:daemon
• npm run typecheck
• lint verification blocked by the local rtk wrapper invoking ESLint instead of the repo's oxlint script