[doowta]

Why

• While the app is connected to a paired computer, a project's menu still offers Open folder.
• The folder is revealed by this computer's file manager, so it opens an unrelated local folder that happens to share the path, or fails when there is none.

What this PR adds

• The project menu offers Open folder only when the app is on this computer. Rename, Trust and Remove go through the connected computer and are unchanged.

Related: independent of the sidebar PRs; #1281 applies the same rule to the task "…" menu.

Details for reviewers (files, checks)

Files (under apps/maple-agent/app/src): ui/chat/sidebar.rs (guard on backend.remote_host()), backend.rs (test-only remote_for_test constructor), ui/chat/tests.rs (only_a_local_project_offers_open_folder: menu on this computer vs. connected to a paired one). 3 files, +53 / −7.

Checks (component Nix shell, Xcode 26.5, on latest master)

• cargo fmt --all -- --check: passed.
• cargo clippy -p maple-agent-app --all-targets --locked -- -D warnings: passed.
• cargo test -p maple-agent-app --locked: 945 passed, 2 ignored.
• The local commit hook was skipped (MAPLE_HOOK_SKIP=1) because of the existing updater test installer::tests::reads_native_release_tar_format_and_preserves_bundle_modes, which fails only on this machine.

🤖 Generated with Claude Code

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