Refactor Commerce B2B skill: rename and flatten directory structure

- Rename skill from create-b2b-commerce-storefront to creating-b2b-commerce-store to better reflect what users actually create (the Store, not the Storefront)
- Flatten directory from skills/commerce/create-b2b-commerce-storefront/ to skills/creating-b2b-commerce-store/ to match repository pattern
- Remove old prompts and rules consolidated into skill
- Update manifest.json with new skill name and paths

manifest.json

@@ -416,6 +416,19 @@
         "references/test-data-factory.md"
       ],
       "description": "Apex test class generation with TestDataFactory patterns, bulk testing (200+ records), mocking strategies for callouts and async operations, and assertion best practices. Use when creating new Apex test classes, improving test coverage, refactoring existing tests, or implementing proper testing patterns for triggers, services, controllers, batch jobs, queueables, and integrations."
+    },
+    {
+      "name": "creating-b2b-commerce-store",
+      "path": "skills/creating-b2b-commerce-store/SKILL.md",
+      "folderPath": "skills/creating-b2b-commerce-store",
+      "category": "commerce",
+      "files": [
+        "SKILL.md",
+        "references/store-vs-storefront.md"
+      ],
+      "description": "Interactive workflow to create Commerce B2B Stores and retrieve storefront metadata. Guides through 7-step process: explaining Store vs Storefront distinction, creating Store in org, listing available sites, selecting storefront, retrieving metadata, and providing deployment guidance. Critical: enforces correct workflow order and prevents manual storefront creation. Use when setting up B2B Commerce stores, retrieving Commerce experiences, or deploying storefronts across orgs.",
+      "license": "Apache-2.0",
+      "compatibility": "Requires Commerce licenses, Experience Cloud, Salesforce CLI"
     }
   ]
 }