fix: use ./ source and simplify plugin.json skills path

Codex review found two issues with the initial fix:
- GitHub source object causes redundant clone, may fail without SSH
- skills paths in plugin.json need ./ prefix

Changed source to "./" (matches Anthropic's own marketplace pattern)
and simplified skills to "./skills" (auto-discovers all skill dirs).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.claude-plugin/marketplace.json

@@ -13,10 +13,7 @@
     {
       "name": "marketing-skills",
       "description": "38 marketing skills for technical marketers and founders: ASO, CRO, copywriting, cold email, SEO, AI SEO, paid ads, ad creative, churn prevention, pricing strategy, referral programs, revenue operations, sales enablement, customer research, site architecture, and more",
-      "source": {
-        "source": "github",
-        "repo": "coreyhaines31/marketingskills"
-      }
+      "source": "./"
     }
   ]
 }

.claude-plugin/plugin.json

@@ -8,44 +8,5 @@
   "homepage": "https://github.com/coreyhaines31/marketingskills",
   "repository": "https://github.com/coreyhaines31/marketingskills",
   "license": "MIT",
-  "skills": [
-    "skills/ab-test-setup",
-    "skills/ad-creative",
-    "skills/ai-seo",
-    "skills/analytics-tracking",
-    "skills/aso-audit",
-    "skills/churn-prevention",
-    "skills/cold-email",
-    "skills/community-marketing",
-    "skills/competitor-alternatives",
-    "skills/competitor-profiling",
-    "skills/content-strategy",
-    "skills/copy-editing",
-    "skills/copywriting",
-    "skills/customer-research",
-    "skills/directory-submissions",
-    "skills/email-sequence",
-    "skills/form-cro",
-    "skills/free-tool-strategy",
-    "skills/launch-strategy",
-    "skills/lead-magnets",
-    "skills/marketing-ideas",
-    "skills/marketing-psychology",
-    "skills/onboarding-cro",
-    "skills/page-cro",
-    "skills/paid-ads",
-    "skills/paywall-upgrade-cro",
-    "skills/popup-cro",
-    "skills/pricing-strategy",
-    "skills/product-marketing-context",
-    "skills/programmatic-seo",
-    "skills/referral-program",
-    "skills/revops",
-    "skills/sales-enablement",
-    "skills/schema-markup",
-    "skills/seo-audit",
-    "skills/signup-flow-cro",
-    "skills/site-architecture",
-    "skills/social-content"
-  ]
+  "skills": "./skills"
 }