refactor(terminology): "deal" → "interest" sweep + route rename

Step 7 per PRE-DEPLOY-PLAN § 1.7. The canonical noun for an in-flight
sales record is "interest" everywhere in the codebase — entity name,
schema, kanban label, URL, etc. Customer-visible "deal" remnants are
either a holdover from pre-refactor copy or hand-written admin
descriptions that drifted.

Sweeps applied:

- /admin/qualification-criteria description: "before a deal moves out
  of the Enquiry stage" → "before an interest moves out…"
- /admin/documenso descriptions (×3): "per-deal upload-and-place…" →
  "per-interest upload-and-place…"; "upload per deal" → "upload per
  interest"; "drafted per deal" → "drafted per interest".
- bulk-archive-wizard.tsx placeholder: "late-stage deal" → "late-stage
  interest".
- smart-archive-dialog.tsx title: "Late-stage deal" → "Late-stage
  interest".
- /api/v1/berths/[id]/deal-documents → /api/v1/berths/[id]/interest-documents
  (route directory renamed; the single in-tree caller in
  berth-deal-documents-tab.tsx updated to match; React Query key also
  switched to "berth-interest-documents" for cache hygiene).

The `BerthDealDocumentsTab` component name + `berth-deal-documents-tab.tsx`
file path are intentionally left as-is — pure aliases, internal to the
codebase, churn cost > readability win. Rename when next touched.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/app/api/v1/berths/[id]/interest-documents/route.ts

@@ -5,7 +5,9 @@ import { errorResponse, NotFoundError } from '@/lib/errors';
 import { listDealDocumentsForBerth } from '@/lib/services/documents.service';
 
 /**
- * GET /api/v1/berths/[id]/deal-documents
+ * GET /api/v1/berths/[id]/interest-documents (renamed from
+ * `/deal-documents` in the 2026-05-14 terminology sweep — canonical
+ * noun is "interest").
  *
  * Lists documents attached to interests currently linked to this berth.
  * Same permission gate as the berth page itself (berths.view).