feat(estimates): template access control — owner can grant edit rights by role or individual

- Add TemplateAccessModal: role-level toggles (All Admins / All Field Agents) + per-person overrides
- Three-state access logic: role grant, individual direct grant, individual exclusion override
- Excluded people (role ON but toggled off) pinned to top with amber 'Excluded' chip
- Direct grants (role OFF but toggled on) show green 'Direct' chip
- canEditTemplates replaces isOwner for all template CRUD guards in EstimatesPage
- Owner retains exclusive access to Manage Access button
- State persisted in mockStore: templateAccessRoles, templateAccessUsers, templateAccessExcluded

src/data/mockStore.jsx

@@ -3639,6 +3639,9 @@ export const MockStoreProvider = ({ children }) => {
     const [dispatchLeads, setDispatchLeads] = useState(DISPATCH_LEADS_INITIAL);
     const [templates, setTemplates] = useState(MASTER_TEMPLATES_INITIAL);
     const [estimates, setEstimates] = useState(MOCK_ESTIMATES_INITIAL);
+    const [templateAccessRoles, setTemplateAccessRoles] = useState([]);
+    const [templateAccessUsers, setTemplateAccessUsers] = useState([]);
+    const [templateAccessExcluded, setTemplateAccessExcluded] = useState([]);
 
     // Initialize properties once
     useEffect(() => {
@@ -3752,6 +3755,12 @@ export const MockStoreProvider = ({ children }) => {
             deleteTemplate: (id) => {
                 setTemplates(prev => prev.filter(t => t.id !== id));
             },
+            templateAccessRoles,
+            templateAccessUsers,
+            templateAccessExcluded,
+            setTemplateAccessRoles,
+            setTemplateAccessUsers,
+            setTemplateAccessExcluded,
 
             // Estimates
             estimates,