Coordinator reliability, browser fixes, and design system overhaul

Features

• Sandbox bash exit code aliases: The bash JSON wrapper now exposes exit code aliases, making it easier to inspect and handle subprocess results programmatically.

Improvements

• Design system and navigation overhaul: Completed a design system audit and overhauled the navigation, resolving all UI contract violations introduced during the remote merge. Pre-commit hooks were added to catch regressions going forward.

Fixes

• Coordinator cancel and loop detection: Cancel operations now stick reliably, and loop detection correctly handles varying error message text that previously caused it to miss repeated failures.
• Discover search and catalog for all callers: Admin users and callers without a team assignment now receive usable search results and a populated catalog instead of empty or error states.
• Browser tool schemas: Corrected tool schemas and browser tool definitions to ensure browser-based tools are invoked with valid parameters.
• DM routing and connector guidance: Fixed send_message routing in the tools-by-code layer and improved connector guidance for direct message flows.
• Web inline error display: Added the missing AppInlineErrorAlert component and corrected template comment placement so inline errors render correctly across the UI.