feat: Complete fleet — 94 skills across 10+ domains

Pulled ALL skills from 15 source repositories:
- anthropics/skills: 16 (docs, design, MCP, testing)
- obra/superpowers: 14 (TDD, debugging, agents, planning)
- coreyhaines31/marketingskills: 25 (marketing, CRO, SEO, growth)
- better-auth/skills: 5 (auth patterns)
- vercel-labs/agent-skills: 5 (React, design, Vercel)
- antfu/skills: 16 (Vue, Vite, Vitest, pnpm, Turborepo)
- Plus 13 individual skills from various repos

Mosaic Stack is not limited to coding — the Orchestrator and
subagents serve coding, business, design, marketing, writing,
logistics, analysis, and more.

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

skills/vercel-composition-patterns/rules/patterns-explicit-variants.md

@@ -0,0 +1,100 @@
+---
+title: Create Explicit Component Variants
+impact: MEDIUM
+impactDescription: self-documenting code, no hidden conditionals
+tags: composition, variants, architecture
+---
+
+## Create Explicit Component Variants
+
+Instead of one component with many boolean props, create explicit variant
+components. Each variant composes the pieces it needs. The code documents
+itself.
+
+**Incorrect (one component, many modes):**
+
+```tsx
+// What does this component actually render?
+<Composer
+  isThread
+  isEditing={false}
+  channelId='abc'
+  showAttachments
+  showFormatting={false}
+/>
+```
+
+**Correct (explicit variants):**
+
+```tsx
+// Immediately clear what this renders
+<ThreadComposer channelId="abc" />
+
+// Or
+<EditMessageComposer messageId="xyz" />
+
+// Or
+<ForwardMessageComposer messageId="123" />
+```
+
+Each implementation is unique, explicit and self-contained. Yet they can each
+use shared parts.
+
+**Implementation:**
+
+```tsx
+function ThreadComposer({ channelId }: { channelId: string }) {
+  return (
+    <ThreadProvider channelId={channelId}>
+      <Composer.Frame>
+        <Composer.Input />
+        <AlsoSendToChannelField channelId={channelId} />
+        <Composer.Footer>
+          <Composer.Formatting />
+          <Composer.Emojis />
+          <Composer.Submit />
+        </Composer.Footer>
+      </Composer.Frame>
+    </ThreadProvider>
+  )
+}
+
+function EditMessageComposer({ messageId }: { messageId: string }) {
+  return (
+    <EditMessageProvider messageId={messageId}>
+      <Composer.Frame>
+        <Composer.Input />
+        <Composer.Footer>
+          <Composer.Formatting />
+          <Composer.Emojis />
+          <Composer.CancelEdit />
+          <Composer.SaveEdit />
+        </Composer.Footer>
+      </Composer.Frame>
+    </EditMessageProvider>
+  )
+}
+
+function ForwardMessageComposer({ messageId }: { messageId: string }) {
+  return (
+    <ForwardMessageProvider messageId={messageId}>
+      <Composer.Frame>
+        <Composer.Input placeholder="Add a message, if you'd like." />
+        <Composer.Footer>
+          <Composer.Formatting />
+          <Composer.Emojis />
+          <Composer.Mentions />
+        </Composer.Footer>
+      </Composer.Frame>
+    </ForwardMessageProvider>
+  )
+}
+```
+
+Each variant is explicit about:
+
+- What provider/state it uses
+- What UI elements it includes
+- What actions are available
+
+No boolean prop combinations to reason about. No impossible states.