feat: AI assistant (HartBOT), demand filling, budget-per-role, project favorites, and UX improvements

AI Assistant (HartBOT):
- Chat panel with inline layout, session persistence, message history (up-arrow recall)
- OpenAI function calling with 20+ tools (search, navigate, create/cancel allocations, update status)
- RBAC-aware tool filtering, fuzzy search with word-level matching
- Navigation actions (router.push) and data invalidation after mutations
- Country/metro city/org unit/role filtering on resource search

Demand Filling Enhancements:
- Two-phase fill modal: plan multiple resources, then confirm & assign all at once
- Availability preview per resource (available/partial/conflict days, existing bookings)
- Coverage bar showing demand hours distribution across assigned resources
- Fill demand from project detail page (new Assign button per demand)
- Fixed: filled demands no longer shown on timeline, demand bars no longer overlap

Budget per Role:
- DemandRequirement.budgetCents field (schema + API + UI)
- Project wizard step 3: budget input per role with allocation summary bar
- Project detail: allocated vs booked budget per demand
- Fill demand modal: role budget display with cost estimates
- AllocationModal: budget field for demand editing

Project Favorites:
- User.favoriteProjectIds (JSONB) with toggle API
- Star button on projects list and detail page (optimistic updates)
- "My Projects" dashboard widget (favorites + responsible person projects)

Project Management:
- Edit project from detail page (ProjectModal integration)
- Edit demands from detail page (AllocationModal integration)
- Admin-only project deletion (cascades assignments + demands)
- Create user accounts from admin panel

Timeline Fixes:
- Country multi-select filter with backend support
- URL param sync for same-page navigation (AI assistant integration)
- Demand lane stacking (no more overlapping bars)
- Single-day booking resize handles (always visible, min 6px)
- Single-day resize allowed (start === end)
- "All Clients" toggle (select all / deselect all)

Other Fixes:
- crypto.randomUUID fallback for non-secure contexts
- Chat message limit raised (200 max, client sends last 40)
- Status dropdown portal (no longer clipped by table overflow)
- Cents display restored in budget views (2 decimal places)
- Allocations grouped view with project sub-groups (collapsed by default)
- Server-side resource search for project wizard (no 500 limit)

Co-Authored-By: claude-flow <ruv@ruv.net>

apps/web/src/components/admin/UsersClient.tsx

@@ -65,9 +65,24 @@ type EditState = {
   chapterIds: string;
 };
 
+type CreateState = {
+  name: string;
+  email: string;
+  password: string;
+  systemRole: SystemRole;
+};
+
+const EMPTY_CREATE: CreateState = {
+  name: "",
+  email: "",
+  password: "",
+  systemRole: SystemRole.USER,
+};
+
 export function UsersClient() {
   const [selectedUserId, setSelectedUserId] = useState<string | null>(null);
   const [editState, setEditState] = useState<EditState | null>(null);
+  const [createState, setCreateState] = useState<CreateState | null>(null);
   const [actionError, setActionError] = useState<string | null>(null);
   const [search, setSearch] = useState("");
   const [roleFilter, setRoleFilter] = useState<SystemRole | "">("");
@@ -101,6 +116,15 @@ export function UsersClient() {
     onError: (err) => setActionError(err.message),
   });
 
+  const createUserMutation = trpc.user.create.useMutation({
+    onSuccess: async () => {
+      await utils.user.list.invalidate();
+      setCreateState(null);
+      setActionError(null);
+    },
+    onError: (err) => setActionError(err.message),
+  });
+
   const resetPermissionsMutation = trpc.user.resetPermissions.useMutation({
     onSuccess: async () => {
       await utils.user.list.invalidate();
@@ -221,10 +245,22 @@ export function UsersClient() {
 
   const selectedUser = editState ? allUsers.find((u) => u.id === editState.userId) : null;
 
+  async function handleCreateUser() {
+    if (!createState) return;
+    setActionError(null);
+    await createUserMutation.mutateAsync({
+      name: createState.name,
+      email: createState.email,
+      password: createState.password,
+      systemRole: createState.systemRole,
+    });
+  }
+
   const isPending =
     updateRoleMutation.isPending ||
     setPermissionsMutation.isPending ||
-    resetPermissionsMutation.isPending;
+    resetPermissionsMutation.isPending ||
+    createUserMutation.isPending;
 
   function clearAll() {
     setSearch("");
@@ -245,6 +281,16 @@ export function UsersClient() {
             Manage user roles and permission overrides
           </p>
         </div>
+        <button
+          type="button"
+          onClick={() => { setCreateState({ ...EMPTY_CREATE }); setActionError(null); }}
+          className="inline-flex items-center gap-2 rounded-lg bg-brand-600 px-4 py-2 text-sm font-medium text-white shadow-sm hover:bg-brand-700 transition-colors"
+        >
+          <svg className="h-4 w-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+            <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M12 4v16m8-8H4" />
+          </svg>
+          Create User
+        </button>
       </div>
 
       {/* Filters */}
@@ -350,6 +396,106 @@ export function UsersClient() {
         </table>
       </div>
 
+      {/* Create User Modal */}
+      {createState && (
+        <div className="fixed inset-0 bg-black/50 z-50 flex items-center justify-center p-4">
+          <div className="bg-white dark:bg-gray-900 rounded-xl shadow-2xl w-full max-w-md mx-4 flex flex-col">
+            <div className="flex items-center justify-between px-6 py-4 border-b border-gray-200 dark:border-gray-700">
+              <h2 className="text-lg font-semibold text-gray-900 dark:text-gray-100">
+                Create User
+              </h2>
+              <button
+                type="button"
+                onClick={() => { setCreateState(null); setActionError(null); }}
+                className="text-gray-400 hover:text-gray-600 dark:hover:text-gray-300 text-2xl leading-none"
+              >
+                &times;
+              </button>
+            </div>
+
+            <div className="px-6 py-5 space-y-4">
+              {actionError && (
+                <div className="rounded-lg bg-red-50 dark:bg-red-900/20 border border-red-200 dark:border-red-700 px-3 py-2 text-sm text-red-700 dark:text-red-400">
+                  {actionError}
+                </div>
+              )}
+
+              <div>
+                <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
+                  Name
+                </label>
+                <input
+                  type="text"
+                  value={createState.name}
+                  onChange={(e) => setCreateState({ ...createState, name: e.target.value })}
+                  placeholder="Max Mustermann"
+                  className="border border-gray-300 dark:border-gray-600 rounded-lg px-3 py-2 text-sm w-full bg-white dark:bg-gray-800 text-gray-900 dark:text-gray-100 focus:outline-none focus:ring-2 focus:ring-brand-400"
+                />
+              </div>
+
+              <div>
+                <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
+                  Email
+                </label>
+                <input
+                  type="email"
+                  value={createState.email}
+                  onChange={(e) => setCreateState({ ...createState, email: e.target.value })}
+                  placeholder="user@example.com"
+                  className="border border-gray-300 dark:border-gray-600 rounded-lg px-3 py-2 text-sm w-full bg-white dark:bg-gray-800 text-gray-900 dark:text-gray-100 focus:outline-none focus:ring-2 focus:ring-brand-400"
+                />
+              </div>
+
+              <div>
+                <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
+                  Password
+                </label>
+                <input
+                  type="password"
+                  value={createState.password}
+                  onChange={(e) => setCreateState({ ...createState, password: e.target.value })}
+                  placeholder="Min. 8 characters"
+                  className="border border-gray-300 dark:border-gray-600 rounded-lg px-3 py-2 text-sm w-full bg-white dark:bg-gray-800 text-gray-900 dark:text-gray-100 focus:outline-none focus:ring-2 focus:ring-brand-400"
+                />
+              </div>
+
+              <div>
+                <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
+                  Role
+                </label>
+                <select
+                  value={createState.systemRole}
+                  onChange={(e) => setCreateState({ ...createState, systemRole: e.target.value as SystemRole })}
+                  className="border border-gray-300 dark:border-gray-600 rounded-lg px-3 py-2 text-sm w-full bg-white dark:bg-gray-800 text-gray-900 dark:text-gray-100 focus:outline-none focus:ring-2 focus:ring-brand-400"
+                >
+                  {Object.values(SystemRole).map((role) => (
+                    <option key={role} value={role}>{SYSTEM_ROLE_LABELS[role]}</option>
+                  ))}
+                </select>
+              </div>
+            </div>
+
+            <div className="flex items-center justify-end gap-3 px-6 py-4 border-t border-gray-200 dark:border-gray-700">
+              <button
+                type="button"
+                onClick={() => { setCreateState(null); setActionError(null); }}
+                className="px-4 py-2 text-sm text-gray-600 hover:text-gray-800 dark:text-gray-400 dark:hover:text-gray-200"
+              >
+                Cancel
+              </button>
+              <button
+                type="button"
+                onClick={() => void handleCreateUser()}
+                disabled={isPending || !createState.name.trim() || !createState.email.trim() || createState.password.length < 8}
+                className="px-4 py-2 bg-brand-600 text-white rounded-lg hover:bg-brand-700 text-sm font-medium disabled:opacity-50 disabled:cursor-not-allowed"
+              >
+                {createUserMutation.isPending ? "Creating..." : "Create User"}
+              </button>
+            </div>
+          </div>
+        </div>
+      )}
+
       {/* Edit Modal */}
       {editState && selectedUser && (
         <div className="fixed inset-0 bg-black/50 z-50 flex items-center justify-center p-4">