fix(app): navigate to selected directory instead of project root when opening sandbox

[bytethm]

Description

When a user opens a directory that belongs to an existing project as a sandbox (e.g., a copied repo with the same git root hash), the app navigates to the project's primary worktree instead of the user-selected directory.

This happens because navigateToProject always navigates to root (the project's worktree from projectRoot()) rather than the directory parameter that was passed in.

Root Cause

• Two separate git repos (e.g. MCP-FRAMEWORKS and MCP-FRAMEWORKS_copy) share the same git root hash
• ProjectV2.resolve generates the same project ID for both
• Project.fromDirectory preserves the existing worktree and adds the new directory as a sandbox
• projectRoot() returns the project worktree, not the sandbox path
• navigateToProject used the worktree as the final navigation target

Fix

Changed the final navigation fallback in navigateToProject from root (project worktree) to directory (the user's actual selected directory). Existing session navigation already correctly uses target.directory, so only the fallback (when no existing session is found) was affected.

Verification

• bun turbo typecheck passes on all 24 packages

[github-actions]

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[github-actions]

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[github-actions]

The following comment was made by an LLM, it may be inaccurate:

The search results show PR #33678 (the current PR) plus a related PR that might be relevant:

Potentially Related PR:

• fix(app): ignore stale project roots when navigating #30685 - fix(app): ignore stale project roots when navigating
  • This addresses project root navigation issues, which is closely related to the current PR's fix for navigating to the correct directory when opening sandboxes.

However, this appears to be a different issue—#30685 focuses on stale project roots, while #33678 fixes the fallback navigation target in navigateToProject. They could be complementary fixes to the same navigation system.

No duplicate PRs found

[bytethm]

撤回，需要进一步排查根因