fix(legacy-stage): purge 9-stage enum keys from rank tables and stale copy

L-001 hunt landed these:

  - src/lib/services/clients.service.ts — stageRank used pre-refactor
    9-stage names exclusively (`contract_signed`, `deposit_10pct`, …).
    Every modern 7-stage interest fell to rank 0, making client-list
    "most-progressed deal" sort effectively random. Modern values now
    own the canonical ranks; legacy aliases map to their 7-stage
    equivalents so historical audit data still sorts.

  - src/lib/services/berth-recommender.service.ts — STAGE_ORDER had
    the same 9-stage shape. LATE_STAGE_THRESHOLD pointed at the (now
    nonexistent) `deposit_10pct` slot. Reworked to the 7-stage scale;
    threshold now at `deposit_paid` (5).

  - Stale comments referencing `deposit_10pct` in schema (clients,
    financial) and client-archive services updated to current copy.

  - Smart-archive dialog rendered `i.pipelineStage` as raw enum; now
    routes through `stageLabelFor` (the new helper added with A2).

Test fixture updates: berth-recommender.test.ts numeric inputs
re-mapped to the new 7-stage scale (eoi_signed=5 → eoi=3, etc.).
1373/1373 vitest pass.

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

src/lib/db/schema/clients.ts

@@ -40,7 +40,7 @@ export const clients = pgTable(
     /** Better-auth user id of the operator who archived this client. */
     archivedBy: text('archived_by'),
     /** Free-text reason captured at archive time. Required when archiving a
-     *  client at deposit_10pct or later (compliance trail). Optional when
+     *  client at deposit_paid or later (compliance trail). Optional when
      *  archiving an early-stage lead. */
     archiveReason: text('archive_reason'),
     /** Per-decision metadata captured during smart-archive flow. Used by