Add a PIREP flag for ready_only; some more METAR cleanup

app/Models/Pirep.php

@@ -39,6 +39,7 @@ use PhpUnitsOfMeasure\Exception\NonStringUnitName;
  * @property Carbon      submitted_at
  * @property Carbon      created_at
  * @property Carbon      updated_at
+ * @property bool        state
  * @package App\Models
  */
 class Pirep extends Model
@@ -174,6 +175,14 @@ class Pirep extends Model
         }
     }
 
+    /**
+     * Return if this PIREP can be edited or not
+     */
+    public function getReadOnlyAttribute(): bool
+    {
+        return $this->state !== PirepState::PENDING;
+    }
+
     /**
      * Return a new Fuel unit so conversions can be made
      * @return int|Fuel