feat: add deposit edit and delete for pending deposits

Add PUT /api/v1/dca/deposits/{id} endpoint to update amount, currency,
and notes on pending deposits. Add DELETE endpoint to remove deposits
not yet inserted into the machine. Both endpoints reject confirmed
deposits. Frontend now shows edit/delete buttons only for pending rows.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

templates/satmachineadmin/index.html

@@ -192,12 +192,21 @@
                   <q-tooltip>Confirm Deposit</q-tooltip>
                 </q-btn>
                 <q-btn
+                  v-if="props.row.status === 'pending'"
                   flat dense size="sm" icon="edit"
                   color="orange"
                   @click="editDeposit(props.row)"
                 >
                   <q-tooltip>Edit Deposit</q-tooltip>
                 </q-btn>
+                <q-btn
+                  v-if="props.row.status === 'pending'"
+                  flat dense size="sm" icon="delete"
+                  color="red"
+                  @click="deleteDeposit(props.row)"
+                >
+                  <q-tooltip>Delete Deposit</q-tooltip>
+                </q-btn>
               </q-td>
             </q-tr>
           </template>