feat: Enhance exam management features and add sensitive word filtering

- Implement global sensitive word filtering in HitokotoCard component.
- Add a test button for Jinrishici API in HitokotoSettings component.
- Introduce ConciseExamCard and ExamScheduleCard components for better exam display.
- Add functionality to create and manage exam configurations in examschedule.vue.
- Implement upcoming exam notifications in the main index page.
- Create a new exam store for managing exam data and fetching exam details.
- Add RelativeTimeDisplay component for displaying relative time in a user-friendly format.

src/components/home/HomeActions.vue

@@ -24,16 +24,26 @@
     >
       随机点名
     </v-btn>
-    <v-btn
+    <v-btn-group
       v-if="showExamScheduleButton"
       class="ml-2"
       color="green"
-      prepend-icon="mdi-calendar-check"
-      size="large"
-      @click="$router.push('/examschedule')"
+      variant="elevated"
+      divided
     >
-      考试看板
-    </v-btn>
+      <v-btn
+        prepend-icon="mdi-calendar-check"
+        size="large"
+        @click="$router.push('/examschedule')"
+      >
+        考试看板
+      </v-btn>
+      <v-btn
+        icon="mdi-plus"
+        size="large"
+        @click="$emit('add-exam-card')"
+      />
+    </v-btn-group>
     <v-btn
       v-if="showListCardButton"
       class="ml-2"