Live v2: root manifest, mount-ack protocol, AST scaffolder, mechanical accept

A ground-up hardening of live mode, driven by a production session in a
nested-app monorepo that hit six distinct failure classes. Full design
rationale in docs/LIVE-REWRITE-PLAN.md; every Codex-reported failure now
has a mechanical fix and a regression test.

Roots: live/roots.mjs resolves appRoot/repoRoot/contextRoot once at boot
(keyed on dev-server configs, not monorepo brand markers), persists a
manifest, and every live CLI re-anchors onto it at startup, so a helper
run from the wrong directory can no longer fork session state. Context
files are discovered upward to the git root.

Render truth: variant_mounted / variant_mount_failed events give the
journal per-variant mount state; failures reach the agent's poll queue,
raise a persistent error card with Retry (no more localStorage wipe), and
an attach probe names root/dev-server mismatches explicitly. The browser
rehydrates from the server when localStorage is gone.

Svelte: the scaffolder now parses with the app's own svelte 5 compiler.
Control flow survives (an each collection crosses the contract as one
structured prop), keyed each blocks hydrate synthetic keys, and anything
a detached preview cannot support falls back to source-preview instead of
shipping a wrong scaffold. Preview modules live in per-publish revision
directories, defeating stale transform caches.

Accept: CSS is reconciled, not appended. Matching selectors are replaced,
params bake from params.json kinds, the compiler's unused-selector pass
prunes superseded rules (pre-existing dead rules protected), a selector-
loss postcondition refuses any write that would drop hand-written rules,
and live-complete refuses to finish while live plumbing remains in source.

Also: framework registry (live/frameworks/) with a crash-safe injection
journal, session-store snapshot caching with read-only reads, protocol
enum consolidation, steer Send button, honest DESIGN-panel empty states.

Testing: new unit suites (roots, AST scaffolder, accept CSS, accept
pipeline, framework conformance); e2e now fails on preview-tree 404s,
proves computed-style mount for every variant, drives the Tune panel
through baked params, and injects failures (broken mounts, republish,
storage loss). New runtime fixtures: monorepo-nested-vite (repo root !=
app root) and vite8-sveltekit-stateful (each blocks + state). Nightly
full-matrix cron. An independent adversarial review pass preceded this
commit; its blocker and major findings are fixed and regression-tested.

This work was produced with AI assistance (Claude Code).

Co-Authored-By: Claude Code <noreply@anthropic.com>

skill/scripts/live/frameworks/sveltekit.mjs

@@ -0,0 +1,71 @@
+/**
+ * SvelteKit registry entry.
+ *
+ * Detection and the apply/remove pair are the existing adapter's
+ * (`../sveltekit-adapter.mjs`); this file only declares them to the registry
+ * and names the artifacts the journal has to be able to heal.
+ */
+
+import {
+  SVELTE_LAYOUT_MARKER_OPEN,
+  SVELTE_LIVE_ROOT_COMPONENT,
+  applySvelteKitLiveAdapter,
+  detectSvelteKitProject,
+  removeSvelteKitLiveAdapter,
+  unpatchSvelteLayout,
+} from '../sveltekit-adapter.mjs';
+
+export const sveltekit = {
+  name: 'sveltekit',
+
+  detect(cwd, config) {
+    return detectSvelteKitProject(cwd, config);
+  },
+
+  inject: {
+    kind: 'adapter',
+
+    apply({ cwd, port, token, config }) {
+      return applySvelteKitLiveAdapter({ cwd, port, token, config });
+    },
+
+    remove({ cwd, config }) {
+      return removeSvelteKitLiveAdapter({ cwd, config });
+    },
+
+    // The generated root component and the `src/lib/impeccable/` runtime paths
+    // are already in the static LIVE_IGNORE_PATTERNS list, so nothing extra.
+    ignorePatterns() {
+      return [];
+    },
+
+    artifacts({ project }) {
+      return [
+        {
+          kind: 'created',
+          path: SVELTE_LIVE_ROOT_COMPONENT,
+          marker: 'impeccable-live-root',
+          pruneTo: 'src',
+        },
+        {
+          kind: 'patched',
+          path: project?.layoutFile || 'src/routes/+layout.svelte',
+          patch: 'sveltekit-layout',
+          markers: [SVELTE_LAYOUT_MARKER_OPEN],
+        },
+      ];
+    },
+
+    unpatch: {
+      'sveltekit-layout': unpatchSvelteLayout,
+    },
+  },
+
+  source: {
+    extensions: ['.svelte'],
+    // Svelte resets component-local state on markup HMR updates, so variants
+    // are mounted from generated components rather than written into the route.
+    preview: 'component',
+    commentSyntax: 'html',
+  },
+};