Fix dashboard data correctness + prebuild embedded SPA

[Exelord]

Summary

User: "your testing needs to be wrong or holes. all data is wrong, works so so, not useful things. and prebuild cloud."

They were right. The previous PRs (#143–#147) "PASS"ed verification because I ran them against /tmp/uitestN workspaces with 2 runs — enough for the app to mount, not enough to surface real data bugs. Driving the dashboard against this repo's actual cache.db (242 runs, 64 entries, 2 projects, 8 tasks) surfaced four real bugs that hit any non-trivial workspace.

Bugs the broader audit found

1. TaskDetail + ProjectDetail were completely broken on any id containing # or / (i.e. every real id like @vzn/vx#test). useParams() from @solidjs/router returns the raw URL-encoded segment; my api layer then re-encoded it, producing %2540vzn%252Fvx%2523test on the wire. Server decoded once and still couldn't split on #. Fix: decode at the page boundary, encode only at the api layer.

2. Cache footprint Treemap was a blank black box. The Treemap renders SVG <rect>; bg-chart-N (background-color) does nothing on SVG. Switched callers to fill-chart-N. The default fallback inside the component also flipped to fill-.

3. UnoCSS safelist was missing the runtime chart palette. paletteFor() generates bg-chart-1..bg-chart-8 at runtime via template literals; UnoCSS's static analyzer can't see them, so the rules were absent. Added bg-/text-/stroke-/fill-/border-chart-{1..8} to the safelist.

4. Overview hero cards defaulted to 24h windows. On a typical workspace where the last run was >24h ago — which describes most workspaces most of the time — every hero showed "Time saved <1ms / 0 hits / 0% rate" despite plenty of cached data. Switched the hero to lifetime totals (always have signal); widened the activity chart to 30 days with day buckets.

Plus

• Parallelism chart x-axis was synthetic indices reading newest-to-oldest (#49 → #0). Replaced with real startedAt timestamps via formatDate.
• getParallelismHistory now filters wall < 50 ms invocations — sub-50 ms cpu/wall ratios are measurement noise and were polluting the average down to ~0.5×.

Prebuilt embedded SPA

User: "prebuild cloud" — interpreted as: a fresh checkout should be able to bun build --compile without first installing 700 npm packages just to build the SPA.

• .gitignore now exempts !apps/ui/dist/
• apps/ui/dist/index.html (130 KB single self-contained HTML) is committed
• The build.ui vx task still regenerates it on UI changes; binaries still embed the freshest version via with { type: 'file' }
• But a checkout that just runs bun build --compile src/bin.ts no longer fails on a missing import

Verification (the protocol that should have been used from day 1)

Drove a Playwright Chromium against the compiled dist/vx-linux-x64 running against this repo's real .vx/cache/cache.db — not a scratch workspace. Captured all 10 pages (Overview, Projects, Project detail for @vzn/vx, Tasks, three Task detail pages — #test, #lint.oxlint, #build.ui, Bottlenecks, Trends, Cache). Zero console / page / request errors after the fixes. Treemap renders. Hero shows lifetime totals. Task/Project detail pages work.

Test plan

• bun src/bin.ts run ci — full gate green (934 tests, 24 metrics tests)
• Playwright audit against real cache.db: 10 pages, 0 errors
• TaskDetail loads for @vzn/vx#test, @vzn/vx#lint.oxlint, @vzn/vx#build.ui
• ProjectDetail loads for @vzn/vx
• Treemap renders with project-colored rectangles
• HBar leaderboard bars colored per project
• Compiled binary serves embedded SPA with prebuilt dist

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Generated by Claude Code