feat(frontend): match dashboard logo to website

[NicholasKissel]

• Replace the dashboard R mark with the website badge in fixed brand colors across light and dark themes.
• Increase the header mark size and reuse it for full-screen route loading states.

[railway-app]

🚅 Deployed to the actors-pr-5609 environment in rivet-frontend

Service	Status	Web	Updated (UTC)
frontend-inspector	😴 Sleeping (View Logs)	Web	Aug 31, 2026 at 9:54 pm
kitchen-sink	😴 Sleeping (View Logs)	Web	Aug 31, 2026 at 9:53 pm
frontend-cloud	😴 Sleeping (View Logs)	Web	Aug 31, 2026 at 9:51 pm
website	❌ Build Failed (View Logs)	Web	Aug 31, 2026 at 9:44 pm
ladle	✅ Success (View Logs)	Web	Aug 27, 2026 at 5:26 pm
mcp-hub	✅ Success (View Logs)	Web	Aug 27, 2026 at 5:24 pm

[claude]

Review

Small, well-scoped visual change (badge-style logo mark to match the website, reused for full-screen loading states). Went through logo.tsx, layout.tsx, top-bar.tsx, and fullscreen-loading.tsx.

Overall: looks correct and clean. No logic changes, no bugs spotted.

Notes (non-blocking)

• LogoMark now hardcodes brand colors (#0F0F0F background / #F0F0F0 fill) instead of stroke="currentColor" + text-foreground, so it intentionally no longer adapts to the app's theme tokens — matches the PR description ("fixed brand colors across light and dark themes"). Per CLAUDE.md's Frontend Visual Changes guidance, worth confirming with agent-browser (or a manual check) that this reads correctly in both light and dark, and across at least OSS and cloud flavors, since a static dark badge can look different against each flavor's chrome.
• frontend/packages/components/src/fullscreen-loading.tsx (the @rivet-gg/components package) still uses the old AssetImage + /logo/icon-white.svg approach and wasn't updated to match this PR's LogoMark swap. It doesn't appear to be a dependency of any app in this repo anymore (no package.json references it, no imports of FullscreenLoading from that package), so it looks like pre-existing dead code rather than something this PR needs to touch — flagging only in case it's still consumed somewhere I couldn't find.
• Switching fullscreen-loading.tsx from an <img>-based asset (icon-white.svg + invert dark:invert-0 classes) to an inline LogoMark SVG is a nice small win: one fewer network request and no theme-dependent CSS filter flicker.

Test coverage

No tests added, which is appropriate here — purely presentational SVG/markup changes with no branching logic.