chore: remove orphaned DesktopPromo component

[detail-app]

Removes the unused DesktopPromo SolidJS component
(packages/console/app/src/component/desktop-promo.tsx) and its companion
stylesheet (desktop-promo.css). These had no production or test consumers:
the only call-site (<DesktopPromo /> in app.tsx) was deliberately removed
in 96ff82a ("fix(console): remove desktop promo overlay"), leaving both
files orphaned. Their shared desktop-tabs-landscape.mp4 asset,
strip from ~/lib/language, and the home.promo.body/home.promo.cta
i18n keys remain used elsewhere (routes/download/index.tsx), so this
deletion has no cascading effect.

Issue for this PR

Closes #

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

Removes dead code: the DesktopPromo overlay component and its CSS were
left orphaned when the overlay's sole consumer was removed in
96ff82a ("fix(console): remove desktop promo overlay"). With no
imports or render references anywhere in the codebase (verified via
codebase-wide grep), neither file is reachable; both are safe to delete.

How did you verify your code works?

• npx tsgo --noEmit (in packages/console/app) passes cleanly.
• bun test (in packages/console/app): 7/7 tests pass.
• git diff --stat confirms only the two intended files are removed
  (163 deletions, no other changes).

Screenshots / recordings

N/A — removal of unreferenced code, no UI behavior change.

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR

AI model: Detail: Dead Code

History

• Last materially changed July 2026 (fix(console): persist desktop promo dismissal anomalyco/opencode#37121 @opencode-agent[bot])

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