feat: add automatic subtask and test result for solution

internal/models/result.go

@@ -5,13 +5,13 @@ import "time"
 type Result int32
 
 const (
-    Testing                 Result = 0
-    NotTested               Result = 1
-    SystemFailDuringTesting Result = 2
-    TimeLimitExceeded       Result = 3
-    MemoryLimitExceeded     Result = 4
-    CompilationError        Result = 5
-    Accepted                Result = 6
+    NotTested               Result = 0 // change only with schema change
+    Accepted                Result = 1
+    CompilationError        Result = 2
+    MemoryLimitExceeded     Result = 3
+    TimeLimitExceeded       Result = 4
+    SystemFailDuringTesting Result = 5
+    Testing                 Result = 6
 )
 
 func (result Result) Valid() error {