feat: share heaps and folders with other users, fix auth and vision pipeline

Sharing:
- New HeapShare and FolderShare models with read/write permissions
- Sharing API router (CRUD for heap and folder shares)
- Heap endpoints accept shared access (photo_ids, add/remove with write)
- Photo list drops user_id filter in shared context, adds owner_username
- Media serving (thumb/original/proxy) falls back to share check on 404
- ShareDialog component for managing shares from kebab menus
- HeapsPanel shows "Shared with me" section for shared heaps
- LeftSidebar shows "Shared with me" section for shared folders
- Owner badge on PhotoThumbnail for photos from other users

Auth:
- Access token default bumped to 1 year, refresh to 10 years
- Refresh token persisted in localStorage (survives page reload)
- Timer-based refresh replaced with 401 axios interceptor

Vision pipeline fixes:
- Bootstrap sets Redis ready key even on partial export failure
- Export functions run conditionally (only for actually missing models)
- _load_thumb handles multi-user path (/data/thumbs/{user_id}/{photo_id}/)
- can_access_photo_via_share uses single subquery instead of N+1 loop

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

frontend/src/components/heaps/HeapsPanel.tsx

@@ -10,15 +10,18 @@ import {
   Pencil,
   Copy,
   Trash2,
+  Users,
 } from 'lucide-react'
 import clsx from 'clsx'
 import { useMutation, useQueryClient } from '@tanstack/react-query'
 import { useHeapsQuery, HEAPS_QUERY_KEY } from '../../hooks/useHeapsQuery'
+import { useSharedHeapsQuery } from '../../hooks/useSharingQueries'
 import { heaps as heapsApi, type Heap } from '../../services/api'
 import { useFilterStore } from '../../store/filterStore'
 import { toast } from '../ToastContainer'
 import { PHOTO_DRAG_MIME } from '../timeline/PhotoThumbnail'
 import { HeapConvertDialog } from './HeapConvertDialog'
+import { ShareDialog } from '../sharing/ShareDialog'
 
 /**
  * Heaps panel for the left sidebar. Renders the list of heaps with the
@@ -43,6 +46,8 @@ export function HeapsPanel() {
   // the drop highlight ring. Only one heap can be the target at a time.
   const [dropTargetId, setDropTargetId] = useState<string | null>(null)
   const [convertingHeap, setConvertingHeap] = useState<Heap | null>(null)
+  const [sharingHeap, setSharingHeap] = useState<Heap | null>(null)
+  const { data: sharedHeaps = [] } = useSharedHeapsQuery()
   // Inline rename state for heap rows: stores the heap id being edited and
   // the draft name. Mirrors the folder rename pattern in LeftSidebar.
   const [renamingId, setRenamingId] = useState<string | null>(null)
@@ -435,6 +440,14 @@ export function HeapsPanel() {
                           setConvertingHeap(heap)
                         }}
                       />
+                      <MenuItem
+                        icon={<Users className="h-3.5 w-3.5" />}
+                        label="Share…"
+                        onClick={() => {
+                          setOpenMenuId(null)
+                          setSharingHeap(heap)
+                        }}
+                      />
                       <div className="my-1 h-px bg-border" />
                       <MenuItem
                         icon={<Trash2 className="h-3.5 w-3.5" />}
@@ -460,10 +473,63 @@ export function HeapsPanel() {
         </div>
       )}
 
+      {/* Shared with me */}
+      {sharedHeaps.length > 0 && expanded && (
+        <div className="mt-1">
+          <div className="px-3 py-0.5 text-[9px] font-semibold uppercase tracking-[0.14em] text-text-faint">
+            Shared with me
+          </div>
+          {sharedHeaps.map((sh) => {
+            const isFiltered = currentSection === `heap-${sh.id}`
+            return (
+              <div
+                key={sh.id}
+                className={clsx(
+                  'group flex h-[24px] cursor-pointer items-center gap-1 rounded px-2 text-[12px] leading-none',
+                  isFiltered ? 'bg-primary/20 text-primary' : 'text-text hover:bg-surface-2',
+                )}
+                style={{ paddingLeft: '20px' }}
+                onClick={() =>
+                  navigateToSection(`heap-${sh.id}`, { heapId: sh.id })
+                }
+              >
+                <Users
+                  className={clsx(
+                    'h-3.5 w-3.5 flex-shrink-0',
+                    isFiltered ? 'text-primary' : 'text-text-muted'
+                  )}
+                />
+                <span className="truncate" title={sh.name}>
+                  {sh.name}
+                </span>
+                <span className="ml-0.5 truncate text-[10px] text-text-faint">
+                  {sh.owner_username}
+                </span>
+                <span className="ml-auto rounded bg-surface-offset px-1 text-[9px] uppercase text-text-faint">
+                  {sh.permission}
+                </span>
+                {sh.photo_count > 0 && (
+                  <span className="flex h-4 min-w-[20px] flex-shrink-0 items-center justify-center rounded bg-surface-offset px-1 text-[10px] tabular-nums text-text-muted">
+                    {sh.photo_count}
+                  </span>
+                )}
+              </div>
+            )
+          })}
+        </div>
+      )}
+
       <HeapConvertDialog
         heap={convertingHeap}
         onClose={() => setConvertingHeap(null)}
       />
+      <ShareDialog
+        isOpen={!!sharingHeap}
+        type="heap"
+        targetId={sharingHeap?.id ?? ''}
+        targetName={sharingHeap?.name ?? ''}
+        onClose={() => setSharingHeap(null)}
+      />
     </div>
   )
 }