Fix visual bugs in expenses page and interest details modal

- Fixed calendar button positioning in date input fields by adding proper padding
- Reduced Current Month button size from large to default for better fit
- Improved export button spacing using ga-4 instead of gap-6
- Removed Save & Close button from InterestDetailsModal, keeping only Save Changes button
- Updated mobile layout to use full width for Save Changes button

components/InterestDetailsModal.vue

@@ -75,18 +75,6 @@
             <v-icon start>mdi-content-save</v-icon>
             Save Changes
           </v-btn>
-          <v-btn
-            variant="outlined"
-            color="success"
-            size="large"
-            @click="() => saveInterest(false, true)"
-            :loading="isSaving"
-            :disabled="isSaving || isDeleting"
-            class="ml-2"
-          >
-            <v-icon start>mdi-content-save-move</v-icon>
-            Save & Close
-          </v-btn>
         </v-toolbar-items>
       </v-toolbar>
 
@@ -227,7 +215,7 @@
                   <span class="text-caption">Delete</span>
                 </v-btn>
               </v-col>
-              <v-col cols="6">
+              <v-col cols="12">
                 <v-btn
                   @click="() => debouncedSaveInterest ? debouncedSaveInterest() : saveInterest()"
                   variant="flat"