fix: improve mobile UX — settings, searchable repos, scrollable table…

[ryancormack]

…s, collapsible tool messages

Addresses multiple UX issues reported when using the app on Android/iOS:

• Add SettingsService (SharedPreferences) with configurable enter key behavior; defaults to enter=newline on mobile, enter=send on web
• Add Settings screen accessible via gear icon in the app bar
• Replace repo selector dropdown with searchable Autocomplete widget while keeping multi-select chip behavior
• Wrap Chats and Tasks tables in horizontal ScrollView to prevent column overlap on narrow screens
• Collapse toolUse and toolResult messages to a single line by default with tap-to-expand; expanded content uses SelectableText so text selection doesn't trigger collapse
• Add expandable/collapsible text for long message segments (>6 lines)
• Improve SessionMessage.fromJson to fall back to JSON encoding for unrecognized content shapes, reducing "(no content)" placeholders

New files:
lib/services/settings_service.dart lib/views/settings_view.dart

Modified:
pubspec.yaml, main.dart, app_shell.dart, home_view.dart, message_input_bar.dart, kiro_api.dart, formatted_content_view.dart, session_detail_view.dart, task_detail_view.dart

I've included the plan for this. I've not done it in Kiro IDE with a full spec - it's mostly 'tweaks' and UI changes.

Expandable Tool Uses:

Kiro specific agent messages:

Expandable agent or user message blocks:

Specific titles for well known tools:

Full UI changes:

Type sortable dropdown for finding repos to attach:

Added 'settings' to allow you to toggle the enter to submit behaviour

(this is a mega annoyance of me. I always press enter by mistake and knowing if shift is pressed on a mobile is annoying)