fix(web): settle the provider update marker once instead of bouncing forever

[rynfar]

The update-available arrow in the provider list ran
[animation:bounce_2.4s_ease-in-out_infinite], so it repainted for as long as the
Providers page stayed open — and Settings is a page people leave open.

Two things wrong with that:

1. AGENTS.md rules the category out. "No continuously repainting animations;
   they peg the GPU on high-refresh displays."
2. Bounce easing reads dated. Real objects decelerate smoothly. Flagged
   independently by the repo's design hook (bounce-easing).

What changes

The cue stays; the loop goes. A named keyframe settles the icon once on
appearance with ease-out-quint (cubic-bezier(0.22, 1, 0.36, 1)), following the
finite-iteration pattern settings-search-target-pulse already establishes in
this stylesheet. motion-reduce:animate-none still disables it.

Verification

• vp test run ProviderInstanceCard.test.ts ProviderSettingsPanel.environment.test.tsx — passing
• vp run -F @t3tools/web typecheck, vp lint — clean
• No infinite animation remains in the file

This came in via a9d75ce1e (merged in #125), restoring an update cue an earlier
refactor had dropped. The cue was right; only its motion needed changing. Left
untouched by the 2026-08-28 upstream batch because no branch in it modified that
line.

Closes #148.

Claude Opus 5 via Claude Code.

---

^{Need help on this PR? Tag @codesmith-bot with what you need. Autofix is disabled.}

[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.3 KiB	13.3 KiB	+1 B (+0.0%)	15.1 KiB	✅
Codex	Thread snapshot wire	6.9 KiB	6.9 KiB	−4 B (−0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.4 KiB	6.4 KiB	+5 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	55.5 KiB	55.5 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	9	9	0 (0.0%)	21	✅
Claude	Total thread wire	13.3 KiB	13.3 KiB	−43 B (−0.3%)	15.1 KiB	✅
Claude	Thread snapshot wire	6.9 KiB	6.9 KiB	+2 B (+0.0%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.4 KiB	6.4 KiB	−45 B (−0.7%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	56.4 KiB	56.3 KiB	−44 B (−0.1%)	66.4 KiB	✅
Claude	Live turn messages	10	9	−1 (−10.0%)	21	✅

Baseline: 71a06e0 · PR result: b17ccf0 · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

• Codex decoded thread snapshot: 109.4 KiB
• Claude decoded thread snapshot: 110.1 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.