chore: snapshot before performance optimization

keep-notes/lib/ai/services/memory-echo.service.ts

@@ -77,11 +77,11 @@ export class MemoryEchoService {
       return [] // Need at least 2 notes to find connections
     }
 
-    // Parse embeddings
+    // Parse embeddings (already native Json from PostgreSQL)
     const notesWithEmbeddings = notes
       .map(note => ({
         ...note,
-        embedding: note.embedding ? JSON.parse(note.embedding) : null
+        embedding: note.embedding ? JSON.parse(note.embedding) as number[] : null
       }))
       .filter(note => note.embedding && Array.isArray(note.embedding))
 
@@ -108,7 +108,7 @@ export class MemoryEchoService {
         }
 
         // Calculate cosine similarity
-        const similarity = cosineSimilarity(note1.embedding, note2.embedding)
+        const similarity = cosineSimilarity(note1.embedding!, note2.embedding!)
 
         // Similarity threshold for meaningful connections
         if (similarity >= similarityThreshold) {
@@ -348,9 +348,9 @@ Explain in one brief sentence (max 15 words) why these notes are connected. Focu
           feedbackType: feedback,
           feature: 'memory_echo',
           originalContent: JSON.stringify({ insightId }),
-          metadata: JSON.stringify({
+          metadata: {
             timestamp: new Date().toISOString()
-          })
+          } as any
         }
       })
     }
@@ -426,8 +426,9 @@ Explain in one brief sentence (max 15 words) why these notes are connected. Focu
       return []
     }
 
-    // Parse target note embedding
-    const targetEmbedding = JSON.parse(targetNote.embedding)
+    // Target note embedding (already native Json from PostgreSQL)
+    const targetEmbedding = targetNote.embedding ? JSON.parse(targetNote.embedding) as number[] : null
+    if (!targetEmbedding) return []
 
     // Check if user has demo mode enabled
     const settings = await prisma.userAISettings.findUnique({
@@ -444,7 +445,8 @@ Explain in one brief sentence (max 15 words) why these notes are connected. Focu
     for (const otherNote of otherNotes) {
       if (!otherNote.embedding) continue
 
-      const otherEmbedding = JSON.parse(otherNote.embedding)
+      const otherEmbedding = otherNote.embedding ? JSON.parse(otherNote.embedding) as number[] : null
+      if (!otherEmbedding) continue
 
       // Check if this connection was dismissed
       const pairKey1 = `${targetNote.id}-${otherNote.id}`