Merge all role-dispatcher pages into single files; add FileBrowser with file-type icons

- DashboardPage, Projects, RequestsPage, ProjectDetailPage, RequestDetail: each now handles team/external/client in one file via role flags — removed 10 old role-specific sub-files
- Layout: client Company nav link goes directly to /company/:id when user has a single company
- FileBrowser: replace emoji icons with colored extension-text badges (square); folder icon stays 📁; Adobe/Figma/design-tool colors for design files
- CompaniesPage: merged team Companies + client company routing (single-company redirect, multi-company list)
- FileSharing: integrated FileBrowser component
- Removed: seafile API + lib, old ServerStatus, TaskDetail, role-split page files

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

src/pages/team/MeetingNotes.jsx

@@ -171,13 +171,14 @@ export default function MeetingNotes() {
                         </div>
                       </div>
                       <LoadingButton
-                        className="btn btn-danger btn-sm"
+                        className="btn-icon btn-icon-danger"
                         loading={deletingId === entry.id}
                         disabled={Boolean(deletingId)}
-                        loadingText="Deleting..."
+                        loadingText="..."
+                        title="Delete"
                         onClick={() => handleDelete(entry)}
                       >
-                        Delete
+                        ✕
                       </LoadingButton>
                     </div>
                     <div className="meeting-note-body">{entry.notes}</div>