fix(unocss): extract utilities from class: directives

[edbfi]

Adds @unocss/extractor-svelte. Without it, a utility used only in a class: directive gets no CSS. Today each of obzorarr's 55 directive utilities also appears somewhere else, so nothing is missing yet; this keeps it that way.

Changes

• Adds @unocss/extractor-svelte (66.10.5, dev) and extractors: [extractorSvelte()].
• .agents/rules/svelte5-sveltekit-app.md is synced from agent-rules@1adb50b. It brings the Wind4 UnoCSS setup (agent-rules#47) and shutdown without a front (agent-rules#46).
• The safelist stays.
  • It was investigated: without it, 40 of its 86 entries are still extracted from source, and the other 46 appear in no source file.
  • But src/lib/server/slides/sanitize.ts:54 allows class on every tag of custom-slide HTML, so stored slides may rely on safelisted utilities.
  • Which utilities custom slides support is a product decision, recorded in edbfi-ci.

Evidence

• Built CSS, before vs. after. bun run build on origin/main and on this branch, then a set-diff of every rule in the client CSS.
  • Only the :root,:host theme variables are reordered; no rule or value changes.
• Directive coverage. I scanned every class:<token> directive in src/ and checked that the built CSS has a rule for it. Before and after, every utility has a rule. The only tokens without one are saving and variant-dark, which are component classes, not utilities.
• bun run check: 0 errors and 0 warnings.
• Review. Codex (gpt-6-astra, high) reviewed this change together with the other four apps and agent-rules#47.
  • Its safelist finding is why obzorarr keeps its safelist: custom slides allow class on user HTML.
  • Its type-cast finding was fixed in the rule.

Not in this PR

• Kit 3's transform_index_html_unsupported warning stays (edbfi-ci D24). SvelteKit never calls UnoCSS's transformIndexHtml hook, and app.html has no utilities, so nothing is lost.
• Dev server: only the first page render after startup includes UnoCSS in the server-rendered styles. Later requests don't, so dev pages can paint unstyled until the client JS loads uno.css. This was measured in all five apps, and moving the import to the root layout didn't fix it. It's recorded in edbfi-ci as a separate investigation.

Owner actions

None.

[pullfrog]

ℹ️ No critical issues found; nothing blocking.

Reviewed changes

Reviewed the full diff of the two commits (4 files).

• uno.config.ts — adds extractors: [extractorSvelte()]. UnoCSS keeps its default extractor alongside custom ones, so this only adds class: directive extraction. The safelist and the ./src/**/*.{html,js,svelte,ts} pipeline are untouched.
• package.json / bun.lock — adds @unocss/extractor-svelte pinned to 66.10.5, matching the other @unocss/* pins. The lock workspace block mirrors package.json.
• .agents/rules/svelte5-sveltekit-app.md — managed rule copy synced from agent-rules@1adb50b (Wind4 setup, shutdown without a front). Not reviewed for content, per repo convention.

Not verified: I couldn't install dependencies or run bun run build in this sandbox, so the built-CSS before/after comparison rests on the PR description. The lock entry's integrity hash and empty dependency map also can't be checked offline.

Nitpick: @unocss/reset (package.json:41) has no import anywhere in the repo. It isn't introduced by this PR, so no change is needed here.

  ^{｜ Fix it ➔ ｜ View workflow run ｜ Using claude-sonnet-5-5 ｜ 𝕏}

[edbfi]

Review nitpick (unused @unocss/reset, package.json:41): REJECTED for this PR. It predates this change and is out of scope here. It's recorded with the S25 follow-ups in edbfi-ci.