feat: publish Tower as an installable Claude Code plugin

.claude-plugin/marketplace.json

@@ -0,0 +1,13 @@
+{
+  "name": "tower-cli",
+  "owner": {
+    "name": "Tower"
+  },
+  "plugins": [
+    {
+      "name": "tower",
+      "source": "./plugin",
+      "description": "Tower compute platform — run and deploy Python apps, pipelines, and AI agents"
+    }
+  ]
+}

.github/workflows/regenerate-skill.yml

@@ -6,7 +6,7 @@ on:
     paths:
       - 'crates/tower-cmd/**'
       - 'crates/tower/**'
-      - 'skills/tower/SKILL.md'
+      - 'plugin/skills/tower/SKILL.md'
       - '.github/workflows/regenerate-skill.yml'
 
 concurrency:
@@ -30,7 +30,7 @@ jobs:
         uses: Swatinem/rust-cache@v2
 
       - name: Regenerate SKILL.md
-        run: cargo run --quiet --bin tower -- skill generate > skills/tower/SKILL.md
+        run: cargo run --quiet --bin tower -- skill generate > plugin/skills/tower/SKILL.md
 
       - name: Open PR if SKILL.md changed
         uses: peter-evans/create-pull-request@v7
@@ -44,4 +44,4 @@ jobs:
           branch: chore/regenerate-skill
           base: develop
           delete-branch: true
-          add-paths: skills/tower/SKILL.md
+          add-paths: plugin/skills/tower/SKILL.md