fix(ui): fit the view after React Flow renders the new layout

[zaebee]

Found by gemini-code-assist on #522, where it was out of scope for a formatting-only PR.

Problem

useLayoutComputation and useFlowNavigation call fitView synchronously, right after the store update that replaces the nodes (setLayout / setFlow). React Flow has not yet rendered or measured the new nodes, so the fit is computed against the previous view.

The visible symptom: clicking a node to open its flow view leaves the viewport zoomed to the 2× cap on the clicked node, with almost everything else off-screen.

Fix

Both calls are deferred to the next animation frame:

requestAnimationFrame(() => void fitView({ padding: 0.15, duration: 250 }));

Measured in the browser

Chromium via Playwright, against vite dev serving the bundled public/graph.json at a 1280×800 viewport. The script counts the nodes whose bounding box lies fully inside the React Flow pane, 1.2 s after each step (fitView animates for 250 ms). Three runs each, and the results were identical across runs:

step	main	this PR
initial load	94 / 94 in view, scale 0.197	94 / 94 in view, scale 0.257 (tighter fit)
click node main → flow view	2 / 95 in view, scale 2 (max zoom)	95 / 95 in view, scale 0.257
console errors	none	none

The initial load was already fully visible on main, but the old fit was looser. It had been computed against stale bounds, too.

Test changed, deliberately

useFlowNavigation.test.ts pinned the synchronous call. It now asserts the fixed contract:

• fitView is not called in the same tick as setFlow;
• it is called with the same options once the frame runs.

The test fails against the old hook.

Test plan

• Playwright before/after measurement above; screenshots were checked visually as well.
• bun run format:check, lint, typecheck, test:run (119 passed), build all pass.
• The updated test fails with the old hook restored.

🤖 Generated with Claude Code

https://claude.ai/code/session_01Uv6LUrB5HCQcqBvmcixYn3

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Generated by Claude Code

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[gemini-code-assist]

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