feat(ui): add info tooltips to all toggles in agent definition editor

[aaight]

Summary

• Adds a new Tooltip UI component suite (web/src/components/ui/tooltip.tsx) built on radix-ui primitives, following the same shadcn/ui pattern as existing components
• Adds an InfoTooltip helper component and enhances the Toggle component with an optional description prop that renders an info icon tooltip
• Wraps AgentDefinitionEditor in <TooltipProvider delayDuration={200}> to enable tooltips throughout the editor
• Adds descriptive tooltip text to all 10 toggles across three sections: Backend (4 toggles + 2 select labels), Trailing Message (5 toggles), and Strategies (1 toggle)

Closes: https://trello.com/c/69a56fcb960f42448baa1e0e

Test plan

• Open the agent definition editor in the dashboard
• Hover over each toggle's info icon in the Backend section — tooltips appear for Enable Stop Hooks, Needs GitHub Token, Block Git Push, Requires PR
• Hover over the Pre-Execute Hook and Post-Configure Hook labels' info icons
• Hover over each toggle in the Trailing Message section — 5 tooltips appear
• Hover over the Include Review Comments toggle in the Strategies section (when gadgetOptions is set)
• Verify tooltips show/hide correctly in both light and dark mode
• Verify all toggles remain functional (clicking still toggles state)
• TypeScript type check passes: cd web && npx tsc -b --noEmit
• Biome lint/format passes: npx @biomejs/biome check web/src/components/settings/...

🤖 Generated with Claude Code

[nhopeatall]

✨ On it — checking the tooltip toggles PR

---

Progress: [██░░░░░░░░] 21% (iteration 15/70)

🔍 Code Review Update (1 min)

I've completed my review of PR #604, focusing on the InfoTooltip component. I verified that the component adheres to existing shadcn/ui patterns, utilizing radix-ui and lucide-react dependencies appropriately. I've approved the pull request as a clean UI enhancement and am now finalizing the session.

_{Last updated: iteration 15 · review}

[nhopeatall]

LGTM — Clean implementation that follows the established shadcn/ui component patterns exactly (radix-ui primitives, data-slot attributes, cn() utility, function components with named exports). The InfoTooltip helper is appropriately scoped as a file-local component, the Toggle enhancement is backward-compatible via the optional description prop, and the TooltipProvider correctly wraps the entire editor tree. All CI checks pass.