feat: el buscador de Proyectos y Actividades tambien busca en tareas

Buscador de Proyectos: ahora busca tambien en actividades y tareas de cualquier proyecto (antes
solo nombre/codigo del proyecto). Resultados en un panel flotante con la ruta completa
"Proyecto - Actividad - Tarea"; clic navega al proyecto y abre la actividad encontrada
(pestaña Tareas si el resultado era una tarea).

Buscador de Actividades (dentro de un proyecto): busca tambien en las tareas de esa actividad,
mismo panel con "Actividad - Tarea".

Nuevo GET /api/search?q=...&projectId= (global o acotado a un proyecto). Nuevos componentes/hooks
reutilizables: SearchResultsDropdown, useDebouncedValue.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

frontend/src/pages/Proyectos/ProjectActivitiesTab.jsx

@@ -1,14 +1,17 @@
-import { useState } from 'react';
+import { useEffect, useRef, useState } from 'react';
 import { Plus, Save, Trash2, ArrowRightLeft } from 'lucide-react';
 import { useUi } from '../../context/ui-context.jsx';
 import { useAuth } from '../../context/auth-context.jsx';
 import { useAsync, useAction } from '../../hooks/useAsync.js';
+import { useDebouncedValue } from '../../hooks/useDebouncedValue.js';
 import { listActivitiesByProject, createActivity, getActivity, deleteActivity, reorderActivities, moveActivity } from '../../services/activities.js';
 import { listProjects } from '../../services/projects.js';
+import { search as searchApi } from '../../services/search.js';
 import { listCatalog } from '../../services/catalogs.js';
 import { listUsers } from '../../services/users.js';
 import { ListView } from '../../components/ListView.jsx';
 import { SearchInput } from '../../components/SearchInput.jsx';
+import { SearchResultsDropdown } from '../../components/SearchResultsDropdown.jsx';
 import { Button } from '../../components/Button.jsx';
 import { Field, FieldRow } from '../../components/Field.jsx';
 import { ComboBox } from '../../components/ComboBox.jsx';
@@ -19,7 +22,7 @@ import ActivityDetailPanel from './ActivityDetailPanel.jsx';
 
 const EMPTY_FORM = { name: '', description: '', responsibleUserId: '', priorityId: '', statusId: '', startDate: '', dueDate: '', isMilestone: false };
 
-export default function ProjectActivitiesTab({ projectId }) {
+export default function ProjectActivitiesTab({ projectId, openActivityId, openActivityTab }) {
   const { t, pushToast, openDialog } = useUi();
   const { user: currentUser } = useAuth();
   const runAction = useAction();
@@ -33,9 +36,40 @@ export default function ProjectActivitiesTab({ projectId }) {
   const [creating, setCreating] = useState(false);
   const [form, setForm] = useState(EMPTY_FORM);
   const [selected, setSelected] = useState(null);
+  const [selectedInitialTab, setSelectedInitialTab] = useState(undefined);
   const [moving, setMoving] = useState(null);
   const [targetProjectId, setTargetProjectId] = useState('');
 
+  // Busca tambien tareas de esta actividad (no solo actividades, que ya filtra la tabla mas abajo
+  // via getSearchHaystack) — resultados con su ruta "Actividad - Tarea" en un panel flotante.
+  const debouncedSearch = useDebouncedValue(search, 300);
+  const searchQuery = debouncedSearch.trim();
+  const { data: searchResults } = useAsync(
+    () => (searchQuery.length >= 2 ? searchApi(searchQuery, projectId) : Promise.resolve(null)),
+    [searchQuery, projectId]
+  );
+  const searchItems = searchResults ? [
+    ...searchResults.activities.map((a) => ({
+      key: `a-${a.id}`,
+      breadcrumb: [`${a.code} — ${a.name}`],
+      onClick: () => { setSearch(''); openActivity({ id: a.id }); },
+    })),
+    ...searchResults.tasks.map((tk) => ({
+      key: `t-${tk.id}`,
+      breadcrumb: [`${tk.activity_code} — ${tk.activity_name}`, tk.name],
+      onClick: () => { setSearch(''); openActivity({ id: tk.activity_id }, 'tasks'); },
+    })),
+  ] : null;
+
+  // Llegada desde el buscador global de Proyectos: abre directo la actividad indicada (una sola vez).
+  const openedFromDeepLink = useRef(false);
+  useEffect(() => {
+    if (openedFromDeepLink.current || !openActivityId || !activities) return;
+    openedFromDeepLink.current = true;
+    openActivity({ id: openActivityId }, openActivityTab);
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [openActivityId, activities]);
+
   const priorityOptions = (priorities || []).map((p) => ({ value: p.id, label: p.name }));
   const statusOptions = (statuses || []).map((s) => ({ value: s.id, label: s.name }));
   const userOptions = (users || []).map((u) => ({ value: u.id, label: u.name }));
@@ -54,9 +88,10 @@ export default function ProjectActivitiesTab({ projectId }) {
     });
   }
 
-  async function openActivity(row) {
+  async function openActivity(row, initialTab) {
     const full = await getActivity(row.id);
     setSelected(full);
+    setSelectedInitialTab(initialTab);
   }
 
   async function refreshAll() {
@@ -137,7 +172,12 @@ export default function ProjectActivitiesTab({ projectId }) {
   return (
     <div>
       <div className="toolbar">
-        <SearchInput value={search} onChange={setSearch} />
+        <div style={{ position: 'relative' }}>
+          <SearchInput value={search} onChange={setSearch} />
+          {searchQuery.length >= 2 && searchItems && (
+            <SearchResultsDropdown items={searchItems} emptyLabel={t('common_search_no_results')} />
+          )}
+        </div>
         <Button variant="accent" icon={Plus} onClick={() => setCreating(true)}>{t('activity_new')}</Button>
       </div>
 
@@ -214,6 +254,7 @@ export default function ProjectActivitiesTab({ projectId }) {
             projectId={projectId}
             siblingActivities={activities}
             onChanged={refreshAll}
+            initialTab={selectedInitialTab}
           />
         )}
       </DetailPopup>