feat(swarm,interactions): Add federated interaction endpoints and update branding

- Add new swarm interaction endpoints for follow, unfollow, like, unlike, mention, and repost actions
- Create interactions.ts library module to handle federated interaction logic
- Add swarm post detail endpoint for retrieving individual post information
- Update post interaction routes to support federated operations
- Replace logo.svg with new logotext.svg for updated branding
- Update login page and sidebar components with new branding assets
- Enhance swarm discovery and type definitions to support new interaction patterns
- Update user follow endpoint to work with federated swarm interactions

src/app/api/swarm/interactions/unlike/route.ts

@@ -0,0 +1,63 @@
+/**
+ * Swarm Unlike Endpoint
+ * 
+ * POST: Receive an unlike from another swarm node
+ */
+
+import { NextRequest, NextResponse } from 'next/server';
+import { db, posts } from '@/db';
+import { eq } from 'drizzle-orm';
+import { z } from 'zod';
+
+const swarmUnlikeSchema = z.object({
+  postId: z.string().uuid(),
+  unlike: z.object({
+    actorHandle: z.string(),
+    actorNodeDomain: z.string(),
+    interactionId: z.string(),
+    timestamp: z.string(),
+  }),
+});
+
+/**
+ * POST /api/swarm/interactions/unlike
+ * 
+ * Receives an unlike from another swarm node.
+ */
+export async function POST(request: NextRequest) {
+  try {
+    if (!db) {
+      return NextResponse.json({ error: 'Database not available' }, { status: 503 });
+    }
+
+    const body = await request.json();
+    const data = swarmUnlikeSchema.parse(body);
+
+    // Find the target post
+    const post = await db.query.posts.findFirst({
+      where: eq(posts.id, data.postId),
+    });
+
+    if (!post) {
+      return NextResponse.json({ error: 'Post not found' }, { status: 404 });
+    }
+
+    // Decrement like count (don't go below 0)
+    await db.update(posts)
+      .set({ likesCount: Math.max(0, post.likesCount - 1) })
+      .where(eq(posts.id, data.postId));
+
+    console.log(`[Swarm] Received unlike from ${data.unlike.actorHandle}@${data.unlike.actorNodeDomain} on post ${data.postId}`);
+
+    return NextResponse.json({
+      success: true,
+      message: 'Unlike received',
+    });
+  } catch (error) {
+    if (error instanceof z.ZodError) {
+      return NextResponse.json({ error: 'Invalid request', details: error.issues }, { status: 400 });
+    }
+    console.error('[Swarm] Unlike error:', error);
+    return NextResponse.json({ error: 'Failed to process unlike' }, { status: 500 });
+  }
+}