fix(audit): non-Documenso backlog sweep — port-binding, NULLS NOT DISTINCT, custom merge tokens, company docs

Wave through the remaining audit-final-deferred items that aren't blocked
on the back-burnered Documenso work.

Multi-tenant isolation:
- Storage proxy ProxyTokenPayload gains optional `p` (port slug) claim;
  verifier asserts `key.startsWith(${p}/)`. Defense-in-depth against a
  buggy issuer in some future code path that mixes port scopes — every
  storage key generated by generateStorageKey() already prefixes the
  slug. document-sends opts in for 24h emailed download links; other
  callers continue working unchanged via the optional field.

DB schema reconciliation:
- Migration 0047 rebuilds system_settings unique index with NULLS NOT
  DISTINCT (Postgres 15+) so global settings (port_id IS NULL) are
  uniquely keyed by `key` alone. Surfaced + dedupe'd 65 duplicate
  (storage_backend, NULL) rows that had accumulated from race-prone
  delete-then-insert patterns in ocr-config / settings / residential-
  stages / ai-budget services. All four services converted to true
  onConflictDoUpdate upserts so the race window is closed.

API uniformity:
- Response shape standardization: 16 routes converted from
  `{ success: true }` to 204 No Content. CLAUDE.md documents the
  convention (`{ data: <T> }` for content, 204 for empty mutations,
  portal-auth retains `{ success: true }` for the frontend's auth chain).
- req.json() → parseBody() migration across 9 admin/CRM routes
  (custom-fields, expenses/export ×3, currency convert,
  search/recently-viewed, admin/duplicates, berths/pdf-{upload-url,
  versions, parse-results}). Uniform 400 error shapes for
  ZodError-flagged bodies.

Custom-fields merge tokens (shipped end-to-end):
- merge-fields.ts gains CUSTOM_MERGE_TOKEN_RE + helpers for the
  `{{custom.<fieldName>}}` shape.
- document-templates validator accepts the dynamic shape alongside
  the static catalog tokens.
- document-sends.service mergeCustomFieldValues resolver fetches
  per-port custom_field_definitions for client/interest/berth contexts
  and substitutes stored values keyed by `{{custom.fieldName}}`.
- custom-fields-manager amber banner updated to reflect that merge
  tokens now expand (search index + entity-diff remain documented
  design limitations).

/api/v1/files cross-entity filtering:
- Validator + listFiles + uploadFile accept companyId AND yachtId
  alongside clientId. file-upload-zone propagates both.
- New CompanyFilesTab component mirrors ClientFilesTab; restored as a
  visible Documents tab in company-tabs.tsx (was a hidden stub).

Inline TODOs:
- Reviewed remaining two TODOs (per-user reminder schedule, import
  worker handlers). Both are placeholders for future feature surfaces,
  not bugs — per-port digest works for every customer; nothing
  currently enqueues import jobs (verified). Annotated in BACKLOG.

BACKLOG.md updated to reflect what landed and what's still pending
(Documenso-related items still bundled with the back-burnered phases).

Tests: 1185/1185 vitest, tsc clean.

src/components/files/file-upload-zone.tsx

@@ -16,6 +16,8 @@ interface FileUploadZoneProps {
   entityType?: string;
   entityId?: string;
   clientId?: string;
+  yachtId?: string;
+  companyId?: string;
   onUploadComplete?: () => void;
 }
 
@@ -23,6 +25,8 @@ export function FileUploadZone({
   entityType,
   entityId,
   clientId,
+  yachtId,
+  companyId,
   onUploadComplete,
 }: FileUploadZoneProps) {
   const [isDragOver, setIsDragOver] = useState(false);
@@ -46,6 +50,8 @@ export function FileUploadZone({
             formData.append('file', file);
             formData.append('filename', file.name);
             if (clientId) formData.append('clientId', clientId);
+            if (yachtId) formData.append('yachtId', yachtId);
+            if (companyId) formData.append('companyId', companyId);
             if (entityType) formData.append('entityType', entityType);
             if (entityId) formData.append('entityId', entityId);
 
@@ -54,8 +60,7 @@ export function FileUploadZone({
             );
 
             // Use fetch directly for FormData (apiFetch JSON-encodes body)
-            const portId = (await import('@/stores/ui-store'))
-              .useUIStore.getState().currentPortId;
+            const portId = (await import('@/stores/ui-store')).useUIStore.getState().currentPortId;
             const headers = new Headers();
             if (portId) headers.set('X-Port-Id', portId);
             const uploadRes = await fetch('/api/v1/files/upload', {
@@ -73,9 +78,7 @@ export function FileUploadZone({
             );
           } catch {
             setUploading((prev) =>
-              prev.map((u) =>
-                u.id === uploadId ? { ...u, error: 'Upload failed' } : u,
-              ),
+              prev.map((u) => (u.id === uploadId ? { ...u, error: 'Upload failed' } : u)),
             );
           }
         }),
@@ -87,7 +90,7 @@ export function FileUploadZone({
         onUploadComplete?.();
       }, 1500);
     },
-    [clientId, entityType, entityId, onUploadComplete],
+    [clientId, yachtId, companyId, entityType, entityId, onUploadComplete],
   );
 
   const handleDrop = useCallback(
@@ -135,9 +138,7 @@ export function FileUploadZone({
       >
         <Upload className="h-8 w-8 text-muted-foreground mb-2" />
         <p className="text-sm font-medium">Drop files here or click to upload</p>
-        <p className="text-xs text-muted-foreground mt-1">
-          PDF, Word, Excel, images up to 50MB
-        </p>
+        <p className="text-xs text-muted-foreground mt-1">PDF, Word, Excel, images up to 50MB</p>
         <input
           ref={inputRef}
           type="file"
@@ -169,9 +170,7 @@ export function FileUploadZone({
               {u.error && (
                 <button
                   type="button"
-                  onClick={() =>
-                    setUploading((prev) => prev.filter((x) => x.id !== u.id))
-                  }
+                  onClick={() => setUploading((prev) => prev.filter((x) => x.id !== u.id))}
                 >
                   <X className="h-3.5 w-3.5 text-muted-foreground" />
                 </button>