feat(core-eslint): use-case name helper (file slug → manifest key)

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

@@ -0,0 +1,17 @@
+/**
+ * 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("");
+}