fix: remove re-introduced skills array from marketplace.json, bump plugin to v1.9.0

PR #264 was based on pre-fix main and re-introduced the inline skills
array that #273 removed. plugin.json with "skills": "./skills" is
the authority.

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

.claude-plugin/marketplace.json

@@ -13,49 +13,7 @@
     {
       "name": "marketing-skills",
       "description": "40 marketing skills for technical marketers and founders: ASO, CRO, copywriting, cold email, SEO, AI SEO, paid ads, ad creative, video production, image generation, churn prevention, pricing strategy, referral programs, revenue operations, sales enablement, customer research, site architecture, and more",
-      "source": "./",
-      "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/image",
-        "./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/video"
-      ]
+      "source": "./"
     }
   ]
 }

.claude-plugin/plugin.json

@@ -1,7 +1,7 @@
 {
   "name": "marketing-skills",
   "description": "Marketing skills for AI agents — conversion optimization, copywriting, SEO, paid ads, ad creative, and growth",
-  "version": "1.8.0",
+  "version": "1.9.0",
   "author": {
     "name": "Corey Haines"
   },