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.

version/version_test.go

@@ -0,0 +1,19 @@
+package version
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestInitDefaults_AreSet(t *testing.T) {
+	if Version == "" {
+		t.Fatal("Version should be initialized")
+	}
+	if Date == "" {
+		t.Fatal("Date should be initialized")
+	}
+	if !strings.Contains(Version, ".") {
+		t.Fatalf("Version should look semantic-ish, got %q", Version)
+	}
+}
+