feat(posts): Add swarm reply tracking and thread visualization

- Add swarm reply metadata fields (swarmReplyToId, swarmReplyToContent, swarmReplyToAuthor) to posts table for tracking replies to federated posts
- Extend swarmReplyTo schema to include optional content and author information for context preservation
- Build synthetic replyTo objects from swarm reply metadata to unify local and federated reply handling
- Include media in replyTo relations across all post queries for complete reply context
- Add thread container styling with visual line connector between parent and child posts
- Implement thread parent display mode with reduced opacity and hidden actions for context
- Add showThread and isThreadParent props to PostCard for flexible thread rendering
- Enable inline parent post visualization when viewing post details to show conversation context

src/lib/types.ts

@@ -50,11 +50,16 @@ export interface Post {
     linkPreviewTitle?: string | null;
     linkPreviewDescription?: string | null;
     linkPreviewImage?: string | null;
-    replyTo?: {
-        author: {
-            handle: string;
-            displayName: string;
-        };
+    replyTo?: Post | null;
+    replyToId?: string | null;
+    // Swarm reply info (when replying to a post on another node)
+    swarmReplyToId?: string | null;
+    swarmReplyToContent?: string | null;
+    swarmReplyToAuthor?: {
+        handle: string;
+        displayName?: string | null;
+        avatarUrl?: string | null;
+        nodeDomain?: string | null;
     } | null;
     isLiked?: boolean;
     isReposted?: boolean;