test(frontend): cover ProcessCard and UpdateBanner rendering

[innocarpe]

Summary

Add render tests for two zero-coverage desktop components (123 assertions total):

ProcessCard (process-card-render.test.tsx, 57) — pure component, jsdom:

• ProcessStatusIcon mappings (15): running/done/failed/waiting/stopped → correct icons/aria
• Uncontrolled card (16): data-tone/open/has-body attributes, head-click toggle, aria-expanded
• Controlled (9), hasBody=false (7: no chevron/aria-expanded, click no-op), defaultOpen (2), Escape closes/reopens (5)

UpdateBanner (update-banner-render.test.tsx, 66) — useUpdater mocked via real hook + mocked window.go.main.App bindings + progress pushes (updater-shared-state pattern):

• All 9 status kinds: available/downloading (0%→25% byte-accurate progress)/verifying/authorizing/installing/relaunching/done/error
• Error dispositions 3-way (retryable/recovery/manual), dismiss per-version (older version resurfaces), mac manual hint, deb/elevated paths, disabling mid-flight

Both appended to the test chain in desktop/frontend/package.json.

Issues

None — coverage gap, no issue report.

Verification

• node --import tsx both files — 57 + 66 passed, 0 failed
• tsc --noEmit — clean

Documentation impact

Documentation-impact: none - test-only addition.

Cache impact

Cache-impact: none - test-only; not a cache-sensitive path.
Cache-guard: N/A
System-prompt-review: N/A