feat(skill-packs): add content licenses (CC-BY-4.0) to registry metadata

Skills are often prompt text (content) not code — content licenses like
CC-BY-4.0 fit better than MIT for these. Adds KnownLicenseSchema enum
with both code (MIT, Apache-2.0, ISC, BSD) and content (CC-BY-4.0,
CC-BY-SA-4.0, CC0-1.0) licenses while keeping the field open for custom
SPDX identifiers.

Author: StackMemory Bot (CLI)

src/core/skill-packs/__tests__/parser.test.ts

@@ -112,6 +112,30 @@ describe('parsePackYaml', () => {
     expect(() => parsePackYaml(yaml.dump(bad))).toThrow();
   });
 
+  it('should accept content licenses like CC-BY-4.0', () => {
+    const manifest = {
+      name: 'learning/opportunities',
+      version: '1.0.0',
+      description: 'Learning exercises for AI-assisted coding',
+      author: 'drcathicks',
+      license: 'CC-BY-4.0',
+    };
+    const pack = parsePackYaml(yaml.dump(manifest));
+    expect(pack.manifest.license).toBe('CC-BY-4.0');
+  });
+
+  it('should accept custom license strings', () => {
+    const manifest = {
+      name: 'test/custom',
+      version: '1.0.0',
+      description: 'Custom license pack',
+      author: 'test',
+      license: 'Proprietary',
+    };
+    const pack = parsePackYaml(yaml.dump(manifest));
+    expect(pack.manifest.license).toBe('Proprietary');
+  });
+
   it('should accept all valid runtime types', () => {
     for (const type of ['local', 'e2b', 'cua', 'modal']) {
       const manifest = {

src/core/skill-packs/types.ts

@@ -90,6 +90,32 @@ export const SkillPackExampleSchema = z.object({
 
 export type SkillPackExample = z.infer<typeof SkillPackExampleSchema>;
 
+// ============================================================
+// LICENSE
+// ============================================================
+
+/**
+ * Known licenses for skill packs.
+ * Code licenses (MIT, Apache-2.0, ISC) and content licenses (CC-BY-4.0, CC-BY-SA-4.0)
+ * are both valid — skills are often prompt text (content) rather than executable code.
+ */
+export const KnownLicenseSchema = z.enum([
+  'MIT',
+  'Apache-2.0',
+  'ISC',
+  'BSD-2-Clause',
+  'BSD-3-Clause',
+  'CC-BY-4.0',
+  'CC-BY-SA-4.0',
+  'CC0-1.0',
+  'UNLICENSED',
+]);
+
+export type KnownLicense = z.infer<typeof KnownLicenseSchema>;
+
+/** Accepts known SPDX identifiers or any custom string */
+const LicenseSchema = KnownLicenseSchema.or(z.string().min(1));
+
 // ============================================================
 // PACK NAME (namespace/pack-name)
 // ============================================================
@@ -111,7 +137,7 @@ export const SkillPackManifestSchema = z.object({
   version: SemverSchema,
   description: z.string().min(1),
   author: z.string().min(1),
-  license: z.string().default('MIT'),
+  license: LicenseSchema.default('MIT'),
   runtime: SkillPackRuntimeSchema.optional(),
   ingestion: SkillPackIngestionSchema.optional(),
   ontology: SkillPackOntologySchema.optional(),