[danyaberezun]

Problem

"Agent working" was shown by breathing the row's own folder/branch glyph in the Projects rail and by three pulsing dots in the chat footer. At 14px a dimming glyph reads as "disabled", and the two surfaces used two unrelated signals for the same state.

Approach

One brand badge for both places: the TR monogram inside a ring. The monogram never moves or distorts — a train laps the ring (1.875s), the monogram pulses once per lap (1 → 25% → 1, in step with the train), and three sparks trace the monogram's outline (6.75s). The pulse is what reads at the rail's 14px; the sparks are detail at larger sizes and ride the brand path itself, so there is no hand-drawn geometry. It is pure currentColor SVG, so it wears the row's existing text-primary / text-text-muted, and reduced motion collapses it to the static badge. Chosen from a set of animated mockups reviewed in the browser.

Changes

• components/RunningIcon is the badge itself (no children wrapper); working-train / working-pulse / working-trace keyframes replace the old working breathing in index.css.
• ProjectTree shows the badge in place of the identity glyph while a session runs; StreamIndicator shows it (decorative) instead of the typing dots.
• constants/branding owns BRAND_MARK_PATH; BrandLogo draws from it. New components → constants edge.
• Specs (components, panels, chat, apps/web, e2e), UI-TERMINOLOGY.md, RunningIcon.test.tsx; the live rail e2e asserts the train's animation via running-icon-train.

Screenshots

Same scenario (Projects rail with two running workspaces, chat footer while thinking), dark theme, 420×230 2x — rendered from each branch's real components with its production CSS bundle. Before: breathing identity glyph + typing dots. After: the TR badge (frame caught mid-pulse).

Before	After

Related issues

None.

Checklist

• Fast gates pass: bun run lint, bun run typecheck, bun run test
• E2E suite passes for app-affecting changes (bun run e2e, or bun run e2e:full when touching agent behavior)
• Before/after screenshots are included for frontend changes, or marked not applicable
• Relevant SPEC.md / top-level specs updated to reflect any boundary, contract, or behavior change
• I have read the Contributing guide and agree to the Code of Conduct

[jetbrains-air]

Approved — ready to merge.

[Rinat S (rsolmano)]

Approving. One non-blocking note inline about the rail signals — up to you how to handle it.

[jetbrains-air]

Approved — ready to merge.