fix: Correct OAuth localhost/127.0.0.1 config and fix grapheme counting for Bluesky posts

- Fixed OAuth client configuration to properly use localhost for client_id and 127.0.0.1 for redirect_uris per RFC 8252 and ATproto spec
- Added proper grapheme counting using RichText API instead of character length
- Fixed thread splitting to account for link suffix and thread indicators in grapheme limits
- Added GOOGLE_EMBEDDING_DIMENSIONS env var to all env files
- Added clear-nodes.ts utility script for database management
- Added galaxy node detail page route

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

lib/ai.ts

@@ -9,12 +9,22 @@ if (!process.env.GOOGLE_EMBEDDING_MODEL) {
   throw new Error('GOOGLE_EMBEDDING_MODEL environment variable is required (e.g., gemini-embedding-001)');
 }
 
+if (!process.env.GOOGLE_EMBEDDING_DIMENSIONS) {
+  throw new Error('GOOGLE_EMBEDDING_DIMENSIONS environment variable is required (e.g., 3072)');
+}
+
 const genAI = new GoogleGenerativeAI(process.env.GOOGLE_GENERATIVE_AI_API_KEY);
 
 const embeddingModel = genAI.getGenerativeModel({
   model: process.env.GOOGLE_EMBEDDING_MODEL,
 });
 
+/**
+ * The expected dimension size for embeddings from the configured model.
+ * This must match the actual output dimension of the embedding model.
+ */
+export const EMBEDDING_DIMENSIONS = parseInt(process.env.GOOGLE_EMBEDDING_DIMENSIONS, 10);
+
 /**
  * Generates a vector embedding for a given text using the configured Google embedding model.
  *