chore(db): stop wiping databases with an older schema version

All installations are past schema version 2, so the one-time reset is gone;
data is never deleted on start (demo mode still resets). user_version is kept
for future migrations. Legal test uses an in-memory DB (cleanup race).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/storage/sqlite.go

@@ -6,7 +6,6 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"log/slog"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -58,22 +57,11 @@ func (s *Store) Close() error {
 	return s.db.Close()
 }
 
-// schemaVersion is stored in PRAGMA user_version. Databases from an older version are wiped and rebuilt
-// on start: MindSift is not in production yet, so breaking changes need no migration path.
+// schemaVersion is stored in PRAGMA user_version so later releases can tell which migrations a database
+// already has. (Version 2 once wiped older databases on start; all installations are past that now.)
 const schemaVersion = 2
 
-func (s *Store) resetOutdatedSchema() error {
-	var version int
-	if err := s.db.QueryRow(`PRAGMA user_version`).Scan(&version); err != nil {
-		return err
-	}
-	if version >= schemaVersion {
-		return nil
-	}
-	slog.Warn("Veraltetes Datenbankschema: alle Daten werden gelöscht und neu angelegt", "version", version, "neu", schemaVersion)
-	return s.dropAllTables()
-}
-
+// dropAllTables removes every table; used by the demo mode reset.
 func (s *Store) dropAllTables() error {
 	conn, err := s.db.Conn(context.Background())
 	if err != nil {
@@ -107,9 +95,6 @@ func (s *Store) dropAllTables() error {
 }
 
 func (s *Store) migrate() error {
-	if err := s.resetOutdatedSchema(); err != nil {
-		return fmt.Errorf("reset outdated schema: %w", err)
-	}
 	schema := `
 	PRAGMA journal_mode = WAL;
 	PRAGMA synchronous = NORMAL;

internal/storage/visibility_test.go

@@ -144,8 +144,9 @@ func TestVisibilityFollowsOrganizations(t *testing.T) {
 	}
 }
 
-func TestOutdatedSchemaIsWiped(t *testing.T) {
-	path := filepath.Join(t.TempDir(), "old.db")
+// Existing data must survive a restart, whatever user_version the database carries.
+func TestDataSurvivesRestart(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "keep.db")
 	store, err := NewStore(path)
 	if err != nil {
 		t.Fatalf("NewStore failed: %v", err)
@@ -159,8 +160,8 @@ func TestOutdatedSchemaIsWiped(t *testing.T) {
 		t.Fatalf("reopen failed: %v", err)
 	}
 	defer store.Close()
-	if n, _ := store.CountUsers(); n != 0 {
-		t.Fatalf("outdated database should start empty, found %d users", n)
+	if n, _ := store.CountUsers(); n != 1 {
+		t.Fatalf("data must be kept on restart, found %d users", n)
 	}
 	var v int
 	_ = store.db.QueryRow(`PRAGMA user_version`).Scan(&v)