Allow manual browser navigation from the session pane

[dot-Justin]

Summary

• Adds a session-pane browser address bar for manual browsing, including typed URLs, pasted/full URLs, search-query fallback, page title display, loading state, and navigation error feedback.
• Wires manual navigation through main/preload IPC into the existing BrowserPool and session navigation state flow so agent-driven and manual browsing share the same browser source of truth.
• Adds back, forward, and reload controls backed by WebContents history APIs.
• Adds focused coverage for URL normalization, navigation dispatch/failure handling, and renderer UI behavior.

Details

Manual navigation now flows through BrowserPool.navigate(), which normalizes the input with a shared helper before calling webContents.loadURL(). BrowserPool also emits live navigation state updates (url, title, canGoBack, canGoForward, isLoading) on navigation, load, title, and in-page route events. The existing setOnNavigate path still updates SessionManager.updateNavigationFromUrl(), so manual browsing keeps primarySite and lastUrl coherent for session resume and agent context.

The renderer subscribes to those navigation-state events in AgentPane and renders a compact browser chrome above the embedded browser. Invalid schemes and load failures are surfaced inline without tearing down the session.

Manual testing

Tested manually on Linux/Hyprland with:

• typed URLs
• pasted/full URLs
• search-query fallback
• invalid scheme feedback
• back/forward/reload after manual navigation

Automated testing

• npm run typecheck
• npm run lint (passes with existing repository warnings)
• npm run test (45 files, 345 tests passed; 1 file and 3 tests skipped)

Closes #409

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Summary by cubic

Adds a compact browser address bar to the session pane with manual navigation and history controls. Aligns with #409 by letting users type or paste URLs, search from the bar, and keep navigation state in sync with agent-driven browsing.

• New Features

  • Address bar with typed/pasted URLs, search fallback, page title, loading, and inline error feedback.
  • Back, forward, and reload using WebContents history APIs.
  • Live navigation state (url, title, canGoBack, canGoForward, isLoading) emitted from main and rendered in the pane.
  • New IPC: sessions:get-navigation-state, sessions:navigate, sessions:back, sessions:forward, sessions:reload, and sessions:navigation-state event.

• Refactors

  • All manual input flows through BrowserPool.navigate() using a shared normalizer in shared/browser-navigation.
  • Keeps SessionManager.updateNavigationFromUrl() updates so primarySite/lastUrl stay correct for resume and context.

^{Written for commit 31804c6. Summary will update on new commits.}

[Cheggin]

ooh I was just making this

will work off of this instead hahaha