chore(template): clean-slate template snapshot from bb4a0c7

Curated, product-agnostic snapshot of the post-story-04 tree: demo
content deleted, auth-only reference feature, web-next shell, all gates
green. Product-specific docs, ADRs 027-029, PRDs/epics/archive, editor
library traces, and product naming are curated out; generic template
repairs (coverage provider devDeps, root test:coverage script, live
lint fixes, root-only release-please) are kept. See TEMPLATE.md for
provenance, curation list, and usage.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016j8z4VHjedXDTjEDNg7qHK

packages/core-eslint/rules/_usecase-name.js

@@ -0,0 +1,23 @@
+/**
+ * Derive the manifest use-case key from a use-case file path.
+ *
+ * Convention: `packages/<feature>/src/application/use-cases/<kebab-slug>.use-case.ts`
+ * → manifest.useCases.<camelCaseSlug>
+ *
+ * Returns null for non-use-case files.
+ */
+export function useCaseNameFromFile(filepath) {
+  if (!filepath.endsWith(".use-case.ts")) return null;
+  if (
+    !filepath.includes("/application/use-cases/") &&
+    !filepath.includes("\\application\\use-cases\\")
+  ) {
+    return null;
+  }
+  const base = filepath.split(/[\\/]/).pop();
+  const slug = base.replace(/\.use-case\.ts$/, "");
+  return slug
+    .split("-")
+    .map((part, i) => (i === 0 ? part : part[0].toUpperCase() + part.slice(1)))
+    .join("");
+}