Fixed volunteer filters.

frontend/src/pages/ScheduleBoard.svelte

@@ -414,7 +414,10 @@
                     <div class="board-assign-row">
                       <select bind:value={assignVolID} style="width:auto">
                         <option value={0}>— Select volunteer —</option>
-                        {#each $allVolunteers ?? [] as v}
+                        {#each ($allVolunteers ?? [])
+                          .filter(v => v.department_id === shift.department_id)
+                          .filter(v => !assigned.some(a => a.volunteer.id === v.id))
+                          as v}
                           <option value={v.id}>{v.name}</option>
                         {/each}
                       </select>