fix(settings): default compact composer and right thread docks

[SDSLeon]

Summary

• enable compact terminal composer mode by default
• place thread docks in the right panel by default so composer bubbles are shown
• preserve explicit saved preferences and cover older settings files

Verification

• pnpm exec vitest run src/main/sharedSettingsFile.test.ts
• pnpm exec oxfmt --check src/shared/settings.ts src/main/sharedSettingsFile.test.ts
• pnpm run typecheck
• pnpm run lint
• git diff --check