fix(ui): show spinner on Run Scan button while request is in flight

[Maqbool61]

Closes #199.

Problem

When clicking "Run Scan", there was no visual feedback during the brief
window while the scan was being created. App.tsx called
setScanStatus('running') and setView('scanning') simultaneously
before await startScan() resolved, switching the view to the scanning
screen before any spinner was visible. The IdleView quick-scan button
had no spinner at all.

What changed

frontend/src/components/App.tsx
Added isStarting boolean state that is true only while
startScan() is in flight. setView('scanning') and
setScanStatus('running') now fire after the request resolves, not
before. isStarting is passed down to both Sidebar and IdleView.

frontend/src/components/Sidebar.tsx
Accepts isStarting prop (optional, defaults false). The Run Scan
button is disabled and shows the Loader2 spinner when either
isStarting or isRunning is true. No new imports — Loader2 was
already present.

frontend/src/components/views/IdleView.tsx
Accepts isStarting prop (optional, defaults false). Added Loader2
to the lucide import. The submit button is disabled and shows a spinner
while isStarting is true.

Tests

221 passed, 19 warnings

[NovaCode37]

Thanks for this — the spinner on Run Scan is a nice UX fix and the isStarting handling looks good. 🙌

One blocker before merging: this branch drops the ?target= URL handler in App.tsx (the urlScanStarted useEffect, plus the MODULE_MAP, detectScanType, and normalizeScanTarget imports). That effect was added for the new browser extension — it lets the extension hand a target to the web UI and auto-start a scan, and the extension (currently in review on Firefox Add-ons) depends on it. Merging as-is would remove that feature.

Could you rebase on the latest main and keep that useEffect alongside your spinner change? They live in different spots and don't conflict — the spinner touches handleScan, the extension handler is a separate mount effect right after it. Once it's back, happy to merge. Thanks!

[Maqbool61]

Thanks for this — the spinner on Run Scan is a nice UX fix and the isStarting handling looks good. 🙌

One blocker before merging: this branch drops the ?target= URL handler in App.tsx (the urlScanStarted useEffect, plus the MODULE_MAP, detectScanType, and normalizeScanTarget imports). That effect was added for the new browser extension — it lets the extension hand a target to the web UI and auto-start a scan, and the extension (currently in review on Firefox Add-ons) depends on it. Merging as-is would remove that feature.

Could you rebase on the latest main and keep that useEffect alongside your spinner change? They live in different spots and don't conflict — the spinner touches handleScan, the extension handler is a separate mount effect right after it. Once it's back, happy to merge. Thanks!

Working on fixing those issues