feat: sqlite persistence with goose migrations, flashcard schema, zap logger

- Add SQLite as authoritative store alongside Qdrant (best-effort indexing)
- Use goose for embedded SQL migrations
- Schema matches flashcard format: id(INTEGER PK), note, repos, host, tags, user, context, created
- Replace std log with zap structured logger
- Split registerTools into registerStoreKnowledge + registerSearchKnowledge
- Qdrant index uses SQLite rowid directly as point ID (no SHA256 hash)
- Search enriches Qdrant results from SQLite by ID
- Lowercase auth header before prefix check
- Always handle json.MarshalIndent errors
- NixOS: StateDirectory, sqlitePath to /var/lib/st-pierre/st-pierre.sqlite

qdrant.go

@@ -2,16 +2,30 @@ package main
 
 import (
 	"context"
-	"crypto/sha256"
-	"encoding/json"
 	"fmt"
+	"strconv"
 
-	"github.com/google/uuid"
 	"github.com/qdrant/go-client/qdrant"
 )
 
 const collectionName = "knowledge"
 
+type entry struct {
+	ID      int64    `json:"id"`
+	Note    string   `json:"note"`
+	Repos   []string `json:"repos,omitempty"`
+	Host    string   `json:"host,omitempty"`
+	Tags    []string `json:"tags,omitempty"`
+	User    string   `json:"user,omitempty"`
+	Context string   `json:"context,omitempty"`
+	Created string   `json:"created"`
+}
+
+type searchResult struct {
+	Entry entry   `json:",inline"`
+	Score float32 `json:"score"`
+}
+
 type qdrantStore struct {
 	client   *qdrant.Client
 	embedder *embedder
@@ -33,7 +47,7 @@ func (s *qdrantStore) ensureCollection(ctx context.Context) error {
 	err = s.client.CreateCollection(ctx, &qdrant.CreateCollection{
 		CollectionName: collectionName,
 		VectorsConfig: qdrant.NewVectorsConfig(&qdrant.VectorParams{
-			Size:     1536, // text-embedding-3-small dimension
+			Size:     1536,
 			Distance: qdrant.Distance_Cosine,
 		}),
 	})
@@ -44,63 +58,32 @@ func (s *qdrantStore) ensureCollection(ctx context.Context) error {
 	return nil
 }
 
-type storedKnowledge struct {
-	ID       string         `json:"id"`
-	Content  string         `json:"content"`
-	Metadata map[string]any `json:"metadata,omitempty"`
-}
-
-type searchResult struct {
-	ID       string         `json:"id"`
-	Content  string         `json:"content"`
-	Score    float32        `json:"score"`
-	Metadata map[string]any `json:"metadata,omitempty"`
-}
-
-func (s *qdrantStore) store(ctx context.Context, content string, metadata map[string]any) (*storedKnowledge, error) {
-	vec, err := s.embedder.embedText(ctx, content)
+func (s *qdrantStore) index(ctx context.Context, id int64, note string) error {
+	vec, err := s.embedder.embedText(ctx, note)
 	if err != nil {
-		return nil, fmt.Errorf("embed text: %w", err)
+		return fmt.Errorf("embed text: %w", err)
 	}
 
-	id := uuid.New().String()
 	payload := map[string]*qdrant.Value{
-		"content": qdrant.NewValueString(content),
-	}
-
-	if metadata != nil {
-		metaBytes, err := json.Marshal(metadata)
-		if err != nil {
-			return nil, fmt.Errorf("marshal metadata: %w", err)
-		}
-		payload["_metadata"] = qdrant.NewValueString(string(metaBytes))
-	}
-
-	idHash := sha256.Sum256([]byte(id))
-	idNum := uint64(0)
-	for i := 0; i < 8; i++ {
-		idNum = (idNum << 8) | uint64(idHash[i])
+		"id":      qdrant.NewValueString(strconv.FormatInt(id, 10)),
+		"content": qdrant.NewValueString(note),
 	}
 
 	_, err = s.client.Upsert(ctx, &qdrant.UpsertPoints{
 		CollectionName: collectionName,
 		Points: []*qdrant.PointStruct{
 			{
-				Id:      qdrant.NewIDNum(idNum),
+				Id:      qdrant.NewIDNum(uint64(id)),
 				Vectors: qdrant.NewVectors(vec...),
 				Payload: payload,
 			},
 		},
 	})
 	if err != nil {
-		return nil, fmt.Errorf("upsert point: %w", err)
+		return fmt.Errorf("upsert point: %w", err)
 	}
 
-	return &storedKnowledge{
-		ID:       id,
-		Content:  content,
-		Metadata: metadata,
-	}, nil
+	return nil
 }
 
 func (s *qdrantStore) search(ctx context.Context, query string, limit uint64) ([]searchResult, error) {
@@ -130,14 +113,9 @@ func (s *qdrantStore) search(ctx context.Context, query string, limit uint64) ([
 		}
 
 		if payload := pt.GetPayload(); payload != nil {
-			if v, ok := payload["content"]; ok {
-				r.ID = fmt.Sprintf("%d", pt.GetId().GetNum())
-				r.Content = v.GetStringValue()
-			}
-			if v, ok := payload["_metadata"]; ok {
-				var meta map[string]any
-				if err := json.Unmarshal([]byte(v.GetStringValue()), &meta); err == nil {
-					r.Metadata = meta
+			if v, ok := payload["id"]; ok {
+				if n, err := strconv.ParseInt(v.GetStringValue(), 10, 64); err == nil {
+					r.Entry.ID = n
 				}
 			}
 		}