fix(P1): soft-archive berths instead of hard-delete — F5

Pre-audit, DELETE /api/v1/berths/[id] called `db.delete()` which
permanently dropped the row, cascade-vanished `interest_berths` links,
broke historical audit references, and could 404 the public feed mid-
customer-inquiry. The `berths.archived_at` column existed in the schema
but was never written.

Changes:
  - `archiveBerth(id, portId, { reason }, meta)` is the new canonical
    soft-archive. Requires a reason (min 5 chars). Blocks when an
    active interest still depends on the berth (forces the rep to
    resolve the deal first). Audit-logs the old status + reason.
  - `restoreBerth(...)` reverses it.
  - DELETE route now accepts `{ reason }` and routes to archiveBerth.
  - New POST /api/v1/berths/[id]/restore.
  - `getBerthOptions` + dashboard occupancy / status-distribution
    queries gain `isNull(berths.archivedAt)` so archived moorings
    don't show up in pickers or skew metrics.
  - Legacy `deleteBerth(...)` kept as a thin wrapper around archiveBerth
    so import sites we haven't migrated still work — labeled @deprecated.

Verified live:
  - DELETE w/o reason       → 400 (validation)
  - DELETE w/ "x"           → 400 "Reason must be ≥ 5 characters"
  - DELETE w/ proper reason → 204, row archived, reason persisted
  - DELETE twice            → 409 "Berth is already archived"
  - POST /restore           → 204, archived_at cleared

Follow-up (deferred): apply isNull(archivedAt) to recommendations.ts,
alert-rules.ts, portal.service.ts, report-generators.ts, berth-rules-
engine.ts. The current set covers the visible surfaces; the rest are
secondary aggregators.

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

src/lib/services/dashboard.service.ts

@@ -89,7 +89,8 @@ export async function getKpis(portId: string) {
   const allBerthsRows = await db
     .select({ status: berths.status })
     .from(berths)
-    .where(eq(berths.portId, portId));
+    // F5: archived berths excluded so retired moorings don't dilute denominator.
+    .where(and(eq(berths.portId, portId), isNull(berths.archivedAt)));
 
   const totalBerths = allBerthsRows.length;
   const occupiedBerths = allBerthsRows.filter((b) => b.status === 'sold').length;
@@ -205,7 +206,7 @@ export async function getBerthStatusDistribution(portId: string) {
   const rows = await db
     .select({ status: berths.status, c: sql<number>`count(*)::int` })
     .from(berths)
-    .where(eq(berths.portId, portId))
+    .where(and(eq(berths.portId, portId), isNull(berths.archivedAt)))
     .groupBy(berths.status);
 
   const counts: Record<string, number> = {};