Add tests for main package, manager, and various components

- Introduced unit tests for the main package to ensure compilation.
- Added tests for the manager, including validation of upload sessions and handling of Blender binary paths.
- Implemented tests for job token generation and validation, ensuring security and integrity.
- Created tests for configuration management and database schema to verify functionality.
- Added tests for logger and runner components to enhance overall test coverage and reliability.

internal/logger/logger_test.go

@@ -0,0 +1,35 @@
+package logger
+
+import (
+	"path/filepath"
+	"testing"
+)
+
+func TestParseLevel(t *testing.T) {
+	if ParseLevel("debug") != LevelDebug {
+		t.Fatal("debug should map to LevelDebug")
+	}
+	if ParseLevel("warning") != LevelWarn {
+		t.Fatal("warning should map to LevelWarn")
+	}
+	if ParseLevel("unknown") != LevelInfo {
+		t.Fatal("unknown should default to LevelInfo")
+	}
+}
+
+func TestSetAndGetLevel(t *testing.T) {
+	SetLevel(LevelError)
+	if GetLevel() != LevelError {
+		t.Fatalf("GetLevel() = %v, want %v", GetLevel(), LevelError)
+	}
+}
+
+func TestNewWithFile_CreatesFile(t *testing.T) {
+	logPath := filepath.Join(t.TempDir(), "runner.log")
+	l, err := NewWithFile(logPath)
+	if err != nil {
+		t.Fatalf("NewWithFile failed: %v", err)
+	}
+	defer l.Close()
+}
+