Implement local SQLite index database with repositories

- Add SQLite database connection management with proper error handling
- Implement schema for files, chunks, blobs, and snapshots tables
- Create repository pattern for each database table
- Add transaction support with proper rollback handling
- Integrate database module with fx dependency injection
- Make index path configurable via VAULTIK_INDEX_PATH env var
- Add fatal error handling for database integrity issues
- Update DESIGN.md to clarify file_chunks vs chunk_files distinction
- Remove FinalHash from BlobInfo (blobs are content-addressable)
- Add file metadata support (mtime, ctime, mode, uid, gid, symlinks)

internal/config/config_test.go

@@ -12,7 +12,7 @@ func TestMain(m *testing.M) {
 	if absPath, err := filepath.Abs(testConfigPath); err == nil {
 		_ = os.Setenv("VAULTIK_CONFIG", absPath)
 	}
-	
+
 	code := m.Run()
 	os.Exit(code)
 }
@@ -24,30 +24,30 @@ func TestConfigLoad(t *testing.T) {
 	if configPath == "" {
 		t.Fatal("VAULTIK_CONFIG environment variable not set")
 	}
-	
+
 	// Test loading the config
 	cfg, err := Load(configPath)
 	if err != nil {
 		t.Fatalf("Failed to load config: %v", err)
 	}
-	
+
 	// Basic validation
 	if cfg.AgeRecipient != "age1xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" {
 		t.Errorf("Expected age recipient to be set, got '%s'", cfg.AgeRecipient)
 	}
-	
+
 	if len(cfg.SourceDirs) != 2 {
 		t.Errorf("Expected 2 source dirs, got %d", len(cfg.SourceDirs))
 	}
-	
+
 	if cfg.SourceDirs[0] != "/tmp/vaultik-test-source" {
 		t.Errorf("Expected first source dir to be '/tmp/vaultik-test-source', got '%s'", cfg.SourceDirs[0])
 	}
-	
+
 	if cfg.S3.Bucket != "vaultik-test-bucket" {
 		t.Errorf("Expected S3 bucket to be 'vaultik-test-bucket', got '%s'", cfg.S3.Bucket)
 	}
-	
+
 	if cfg.Hostname != "test-host" {
 		t.Errorf("Expected hostname to be 'test-host', got '%s'", cfg.Hostname)
 	}
@@ -59,9 +59,9 @@ func TestConfigFromEnv(t *testing.T) {
 	if configPath == "" {
 		t.Skip("VAULTIK_CONFIG not set")
 	}
-	
+
 	// Verify the file exists
 	if _, err := os.Stat(configPath); os.IsNotExist(err) {
 		t.Errorf("Config file does not exist at path from VAULTIK_CONFIG: %s", configPath)
 	}
-}
+}