feat(booking-templates): per-company opt-in hiding of system templates (#2004)

* feat(booking-templates): per-company opt-in hiding of system templates

Users cannot delete or hide the 26 standard konteringspaket, which clutter
the settings panel and every template picker. Deletion stays off the table
(shared global rows); instead a company can now hide individual system
templates for itself only.

- New booking_template_hidden table (insert=hide, delete=unhide), RLS gated
  on active company + write role; nothing hidden by default
- POST/DELETE /api/settings/booking-templates/[id]/hide (system templates
  only; company/team templates keep their real delete path)
- List route decorates rows with per-company is_hidden; pickers filter them
  out; the settings panel shows hidden ones in a collapsed restore section
  so hiding is never silent
- Classified in full-archive-export exclusions (UI preference, not
  rakenskapsinformation)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PU1KN431c9gp5zKvFaa1NL

* fix(booking-templates): idempotent re-hide, system-only RLS insert, hidden filter in bulk-book

Skeptic + CodeRabbit findings on #2004, one pass:

- hide upsert now passes ignoreDuplicates (DO NOTHING): the table has no
  UPDATE policy on purpose, so the DO UPDATE conflict arm turned a
  concurrent re-hide into an RLS 42501/500; pg test pins the conflict shape
- bth_insert policy additionally requires the referenced template to be an
  active system template (migration is unmerged, edited in place); negative
  pg test for company templates
- BulkBookDialog excludes templates hidden by the company (was reading the
  table directly and ignoring hides)
- panel shows the failure toast when the hide/unhide fetch itself rejects
- picker category chips built from the hidden-filtered list

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PU1KN431c9gp5zKvFaa1NL

---------

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

components/bookkeeping/BookingTemplatePicker.tsx

@@ -57,7 +57,9 @@ export default function BookingTemplatePicker({ onApply, entityType, defaultAmou
   }, [open, templatesError, toast])
 
   const filtered = useMemo(() => {
-    let result = templates
+    // Templates hidden for this company (opt-in via the settings panel)
+    // never surface in the picker; only settings shows them, for restore.
+    let result = templates.filter((t) => !t.is_hidden)
 
     // Filter by entity type
     if (entityType) {
@@ -82,9 +84,11 @@ export default function BookingTemplatePicker({ onApply, entityType, defaultAmou
     return result
   }, [templates, entityType, selectedCategory, search])
 
-  // Unique categories present in templates
+  // Unique categories present in visible templates. Built from the
+  // hidden-filtered list so a category whose templates are all hidden does
+  // not render a chip that can only ever match nothing.
   const availableCategories = useMemo(() => {
-    const cats = new Set(templates.map((t) => t.category))
+    const cats = new Set(templates.filter((t) => !t.is_hidden).map((t) => t.category))
     return Array.from(cats).sort()
   }, [templates])
 

components/bookkeeping/TemplateBookDialog.tsx

@@ -53,7 +53,11 @@ export default function TemplateBookDialog({ open, onOpenChange, onCreated }: Pr
   // Session-cached (lib/reference-data): opening the dialog costs no
   // requests once the lists are in the cache. null = still loading.
   const { templates: cachedTemplates, isLoading: templatesLoading } = useBookingTemplates()
-  const templates: BookingTemplateLibrary[] | null = templatesLoading ? null : cachedTemplates
+  // Templates hidden for this company (settings panel opt-in) never show in
+  // the booking flow; the settings panel is the only surface that lists them.
+  const templates: BookingTemplateLibrary[] | null = templatesLoading
+    ? null
+    : cachedTemplates.filter((tt) => !tt.is_hidden)
   const { periods } = useFiscalPeriods()
   const [search, setSearch] = useState('')
   const [selected, setSelected] = useState<BookingTemplateLibrary | null>(null)