diff --git a/cmd/main_test.go b/cmd/main_test.go
index 42af976f..00747571 100644
--- a/cmd/main_test.go
+++ b/cmd/main_test.go
@@ -15,9 +15,11 @@ func resetSharedStateDB() error {
 	// Reset any pre-existing global DB state (e.g. left by an init or an
 	// isolated test cleanup) before pointing the package at the shared suite DB.
 	state.CloseDB()
-	err := config.EnsureDirs()
+	if err := config.EnsureDirs(); err != nil {
+		return err
+	}
 	state.Configure(filepath.Join(config.GetStateDir(), "surge.db"))
-	return err
+	return nil
 }
 
 func TestMain(m *testing.M) {
@@ -35,6 +37,7 @@ func TestMain(m *testing.M) {
 
 		if ensureErr := resetSharedStateDB(); ensureErr != nil {
 			fmt.Fprintf(os.Stderr, "TestMain: failed to create isolated Surge test directories: %v\n", ensureErr)
+			_ = os.RemoveAll(tmpDir)
 			os.Exit(1)
 		}
 	}
diff --git a/internal/config/settings.go b/internal/config/settings.go
index d2738b00..7fef40d1 100644
--- a/internal/config/settings.go
+++ b/internal/config/settings.go
@@ -68,19 +68,19 @@ type ExtensionSettings struct {
 
 // NetworkSettings contains network connection parameters.
 type NetworkSettings struct {
-	MaxConnectionsPerDownload int    `json:"max_connections_per_host" ui_label:"Max Connections/Download" ui_desc:"Maximum concurrent connections per download (1-64)."`
+	MaxConnectionsPerDownload int `json:"max_connections_per_host" ui_label:"Max Connections/Download" ui_desc:"Maximum concurrent connections per download (1-64)."`
 	// Deprecated: use MaxConnectionsPerDownload.
 	// Kept as a non-serialized compatibility alias for older code paths and tests.
-	MaxConnectionsPerHost     int    `json:"-" ui_ignored:"true"`
-	MaxConcurrentDownloads    int    `json:"max_concurrent_downloads" ui_label:"Max Concurrent Downloads" ui_desc:"Maximum number of downloads running at once (1-10)." ui_restart:"true"`
-	MaxConcurrentProbes       int    `json:"max_concurrent_probes" ui_label:"Max Concurrent Probes" ui_desc:"Maximum number of simultaneous server probes when adding many downloads at once (1-10)." ui_restart:"true"`
-	UserAgent                 string `json:"user_agent" ui_label:"User Agent" ui_desc:"Custom User-Agent string for HTTP requests. Leave empty for default."`
-	ProxyURL                  string `json:"proxy_url" ui_label:"Proxy URL" ui_desc:"HTTP/HTTPS proxy URL (e.g. http://127.0.0.1:1700). Leave empty to use system default."`
-	CustomDNS                 string `json:"custom_dns" ui_label:"Custom DNS Server" ui_desc:"Set custom DNS (e.g., 1.1.1.1:53, 94.140.14.14:53). Leave empty for system."`
-	SequentialDownload        bool   `json:"sequential_download" ui_label:"Sequential Download" ui_desc:"Download pieces in order (Streaming Mode). May be slower."`
-	MinChunkSize              int64  `json:"min_chunk_size" ui_label:"Min Chunk Size" ui_desc:"Minimum download chunk size in MB (e.g., 2)."`
-	WorkerBufferSize          int    `json:"worker_buffer_size" ui_label:"Worker Buffer Size" ui_desc:"I/O buffer size per worker in KB (e.g., 512)."`
-	DialHedgeCount            int    `json:"dial_hedge_count" ui_label:"Dial Hedge Count" ui_desc:"Number of extra connections to dial pre-emptively to avoid slow connects (0-16)."`
+	MaxConnectionsPerHost  int    `json:"-" ui_ignored:"true"`
+	MaxConcurrentDownloads int    `json:"max_concurrent_downloads" ui_label:"Max Concurrent Downloads" ui_desc:"Maximum number of downloads running at once (1-10)." ui_restart:"true"`
+	MaxConcurrentProbes    int    `json:"max_concurrent_probes" ui_label:"Max Concurrent Probes" ui_desc:"Maximum number of simultaneous server probes when adding many downloads at once (1-10)." ui_restart:"true"`
+	UserAgent              string `json:"user_agent" ui_label:"User Agent" ui_desc:"Custom User-Agent string for HTTP requests. Leave empty for default."`
+	ProxyURL               string `json:"proxy_url" ui_label:"Proxy URL" ui_desc:"HTTP/HTTPS proxy URL (e.g. http://127.0.0.1:1700). Leave empty to use system default."`
+	CustomDNS              string `json:"custom_dns" ui_label:"Custom DNS Server" ui_desc:"Set custom DNS (e.g., 1.1.1.1:53, 94.140.14.14:53). Leave empty for system."`
+	SequentialDownload     bool   `json:"sequential_download" ui_label:"Sequential Download" ui_desc:"Download pieces in order (Streaming Mode). May be slower."`
+	MinChunkSize           int64  `json:"min_chunk_size" ui_label:"Min Chunk Size" ui_desc:"Minimum download chunk size in MB (e.g., 2)."`
+	WorkerBufferSize       int    `json:"worker_buffer_size" ui_label:"Worker Buffer Size" ui_desc:"I/O buffer size per worker in KB (e.g., 512)."`
+	DialHedgeCount         int    `json:"dial_hedge_count" ui_label:"Dial Hedge Count" ui_desc:"Number of extra connections to dial pre-emptively to avoid slow connects (0-16)."`
 }
 
 // PerformanceSettings contains performance tuning parameters.
diff --git a/internal/engine/types/accuracy_test.go b/internal/engine/types/accuracy_test.go
index 27c939aa..33b8f57f 100644
--- a/internal/engine/types/accuracy_test.go
+++ b/internal/engine/types/accuracy_test.go
@@ -94,7 +94,7 @@ func TestRestoreBitmap_ShortBitmapRecoversWithoutPanic(t *testing.T) {
 
 	state := types.NewProgressState("test-short-restore", totalSize)
 	malformed := []byte{0x02} // Too short: only enough storage for 4 chunks.
-	expectedBytes := 25      // 100 chunks * 2 bits = 25 bytes.
+	expectedBytes := 25       // 100 chunks * 2 bits = 25 bytes.
 
 	defer func() {
 		if r := recover(); r != nil {