User can now add, edit, and delete timetables without crashing (hopefully)

.idea/gradle.xml

@@ -7,6 +7,7 @@
         <option name="testRunner" value="GRADLE" />
         <option name="distributionType" value="DEFAULT_WRAPPED" />
         <option name="externalProjectPath" value="$PROJECT_DIR$" />
+        <option name="gradleJvm" value="jbr-17" />
         <option name="modules">
           <set>
             <option value="$PROJECT_DIR$" />

.idea/misc.xml

@@ -1,6 +1,6 @@
 <project version="4">
   <component name="ExternalStorageConfigurationManager" enabled="true" />
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_17" project-jdk-name="jbr-17" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_17" default="true" project-jdk-name="jbr-17" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/build/classes" />
   </component>
   <component name="ProjectType">