feat: deeplink controls + Raycast extension (#1540)

[nitin-rachabathuni]

Closes #1540

Summary

• Fixed cap-desktop://action?... parsing by using host_str() instead of domain() (custom schemes return None for domain)
• Added path-based deeplinks for recording control: record/start, record/stop, record/pause, record/resume, record/toggle-pause
• Added device switching deeplinks: device/microphone?label=... and device/camera?model_id|device_id|label|off
• Pauses active recording before mic/camera switches (matches in-app UI behavior)
• Extracted start_recording_from_saved_settings() for reuse from deeplinks and hotkeys
• Added Raycast extension at apps/raycast/ with Cap Control and Switch Device commands
• Documented all routes in apps/desktop/src-tauri/DEEPLINKS.md
• Added unit tests for deeplink parsing

Testing

• npx tsc --noEmit in apps/raycast/ passes
• Rust unit tests in deeplink_actions (run: cargo test deeplink_actions)
• Manual macOS smoke test: open "cap-desktop://record/pause" with Cap running

Demo

Demo video to follow after macOS manual verification.

/claim #1540

Greptile Summary

This PR adds path-based deeplinks (record/*, device/*) for controlling Cap recordings and switching devices from external tools, fixes the original action host parsing bug (using host_str() instead of domain()), and ships a new Raycast extension that drives those deeplinks via system_profiler device enumeration.

• Rust (deeplink_actions.rs): replaces the broken TryFrom impl with a clean parse_deeplink function, adds PauseRecording, ResumeRecording, TogglePauseRecording, SetMicrophone, SetCamera variants, and a pause_for_input_change helper; unit tests cover all new routes.
• Refactor (lib.rs): extracts start_recording_from_saved_settings() and reuses it from both the RequestStartRecording event handler and the new StartSavedRecording deeplink variant.
• Raycast extension (apps/raycast/): two commands — Cap Control (static action list) and Switch Device (dynamic system_profiler enumeration) — that open or copy deeplinks.

Confidence Score: 3/5

Two correctness bugs need fixing before merge: recordings can be left permanently paused when a device-switch deeplink targets an unknown device, and the Raycast Switch Device command can throw a runtime error by calling showToast after it has been dismissed.

The deeplink parsing refactor and Raycast extension are well-structured and include good test coverage, but both issues are in newly exercised code paths. A user sending cap-desktop://device/camera?label=UnknownCam will silently pause their recording with no recovery path. The showToast issue in switch-device.tsx can surface as an uncaught Raycast runtime error in normal use.

apps/desktop/src-tauri/src/deeplink_actions.rs (SetCamera/SetMicrophone execute handlers) and apps/raycast/src/switch-device.tsx (error handling in useEffect)

Important Files Changed

Filename	Overview
apps/desktop/src-tauri/src/deeplink_actions.rs	Core deeplink parsing refactor: fixes host_str() bug, adds record/device routes, and unit tests — but the SetCamera/SetMicrophone handlers pause first, then validate, leaving the recording paused if the device switch fails.
apps/desktop/src-tauri/src/lib.rs	Extracts start_recording_from_saved_settings() for reuse; refactor preserves original behavior and is straightforward.
apps/raycast/src/switch-device.tsx	Switch Device Raycast command; showToast is called outside the !cancelled guard, risking a Raycast runtime error when the command is dismissed mid-load.
apps/raycast/src/lib/devices.ts	Heuristic system_profiler parser for microphones and cameras; logic is macOS-specific and best-effort but appropriate for the use case.
apps/raycast/src/lib/deeplinks.ts	Static deeplink action registry and openCapDeeplink helper; clean and correct.
apps/raycast/src/cap-control.tsx	Cap Control Raycast command; simple list over static actions, no issues.
apps/raycast/package.json	New Raycast extension package manifest; dependencies look appropriate.

Prompt To Fix All With AI

Fix the following 2 code review issues. Work through them one at a time, proposing concise fixes.

---

### Issue 1 of 2
apps/desktop/src-tauri/src/deeplink_actions.rs:372-383
**Recording left paused on failed device switch**

`pause_for_input_change` runs before the device selector is validated. If `resolve_camera_selector` or `set_mic_input` returns an error, the `?` short-circuits and the recording is left permanently paused — the user has no way to tell why, and no resume is triggered. To fix, resolve and validate the camera/mic label before calling `pause_for_input_change`, then pause only once the switch is confirmed possible.

### Issue 2 of 2
apps/raycast/src/switch-device.tsx:21-33
`showToast` is outside the `!cancelled` guard, so if the component unmounts while `loadDeviceItems` is still in flight and that call rejects, Raycast will receive an API call from a dismissed command, which throws a runtime error.

```suggestion
			} catch (loadError) {
				const message =
					loadError instanceof Error ? loadError.message : String(loadError);
				if (!cancelled) {
					setItems([]);
					setError(message);
					await showToast({
						style: Toast.Style.Failure,
						title: "Failed to enumerate devices",
						message,
					});
				}
			} finally {
```

_{Reviews (1): Last reviewed commit: "feat: add deeplink controls and Raycast ..." | Re-trigger Greptile}

Greptile also left 2 inline comments on this PR.

[superagent-security]

Superagent didn't find any vulnerabilities or security issues in this PR.

[nitin-rachabathuni]

Validation update

Automated checks

• ✅ Raycast extension: npx tsc --noEmit passes
• ✅ Superagent security scan: clean
• ✅ 8 Rust unit tests added in deeplink_actions.rs (parsing + camera resolution)

Manual validation script

Added scripts/demo-bounty-1540.sh on the PR branch — re-run anytime:

./scripts/demo-bounty-1540.sh

Notes

• Legacy cap-desktop://action?value=... deeplinks work on the stock Cap app (demo opens Settings).
• New path-based routes (cap-desktop://record/pause, etc.) require Cap built from this PR — full E2E needs pnpm dev:desktop after sidecar build.
• Rust cargo test deeplink_actions blocked locally by ffmpeg-sys-next bindgen on this macOS 26 env; CI should cover compile + tests.

Happy to iterate on any Greptile/maintainer feedback.

[nitin-rachabathuni]

Addressed both Greptile P1 comments in 22a5613:

1. deeplink_actions.rs — SetMicrophone / SetCamera now resolve and validate the target device before calling pause_for_input_change, so a failed switch no longer leaves the recording paused.
2. switch-device.tsx — showToast moved inside the !cancelled guard to avoid Raycast runtime errors when the command is dismissed mid-load.

Review threads marked resolved.

[nitin-rachabathuni]

Overnight status (no new code changes needed):

• Both Greptile P1 threads remain resolved (22a5613fb)
• Security checks: Contributor trust, Socket, Superagent — all green
• Vercel FAILURE is fork authorization (vercel.com/git/authorize) — expected for external contributors; not a code/build regression from this PR

PR is mergeable from GitHub’s perspective; awaiting maintainer review in a crowded field (#1540).