feat: bulk delete, team dispatch, calendar views, timeline colors

- Multi-select bulk delete in all 5 list views (Artefacts, Posts, Tasks,
  Issues, Assets) with cascade deletes and confirmation modals
- Team-based issue dispatch: team picker on public issue form, team filter
  on Issues page, copy public link from Team page and Issues header,
  team assignment in IssueDetailPanel
- Month/Week toggle on PostCalendar and TaskCalendarView
- Month/Week/Day zoom on project and campaign timelines (InteractiveTimeline)
  and ProjectDetail GanttView, with Month as default
- Custom timeline bar colors: clickable color dot with 12-color palette
  popover on project, campaign, and task timeline bars
- Artefacts default view changed to list
- BulkSelectBar reusable component
- i18n keys for all new features (en + ar)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

client/src/pages/CampaignDetail.jsx

@@ -71,7 +71,7 @@ export default function CampaignDetail() {
 
   useEffect(() => { loadAll() }, [id])
   useEffect(() => {
-    api.get('/campaigns').then(r => setAllCampaigns(Array.isArray(r) ? r : (r.data || []))).catch(() => {})
+    api.get('/campaigns').then(r => setAllCampaigns(Array.isArray(r) ? r : [])).catch(() => {})
   }, [])
 
   const loadAll = async () => {
@@ -82,10 +82,10 @@ export default function CampaignDetail() {
         api.get(`/campaigns/${id}/posts`),
         api.get(`/campaigns/${id}/assignments`),
       ])
-      setCampaign(campRes.data || campRes || null)
-      setTracks(tracksRes.data || tracksRes || [])
-      setPosts(postsRes.data || postsRes || [])
-      setAssignments(Array.isArray(assignRes) ? assignRes : (assignRes.data || []))
+      setCampaign(campRes)
+      setTracks(Array.isArray(tracksRes) ? tracksRes : [])
+      setPosts(Array.isArray(postsRes) ? postsRes : [])
+      setAssignments(Array.isArray(assignRes) ? assignRes : [])
     } catch (err) {
       console.error('Failed to load campaign:', err)
     } finally {
@@ -96,7 +96,7 @@ export default function CampaignDetail() {
   const loadUsersForAssign = async () => {
     try {
       const users = await api.get('/users/team?all=true')
-      setAllUsers(Array.isArray(users) ? users : (users.data || []))
+      setAllUsers(Array.isArray(users) ? users : [])
     } catch (err) {
       console.error('Failed to load users:', err)
     }