Add real digital_ads + digital_branding catalogs

Built from real D.intelligence docs (not the 견적 자료 folder, which has only
GA4/GTM + education — confirmed):
- digital_branding: TNS 유학원 디지털 브랜딩 진단 컨설팅 → ₩9,000,000 (5 fixed stages)
- digital_ads: 디하이브 디지털 광고·퍼포먼스 마케팅 대행 계약 → ₩6,000,000/월 retainer
  (media-spend commission % is per-deal, kept as a parameter — not invented)

effort method now supports fixed-amount tasks (Unit Cost) and monthly retainers
(unit: monthly); render shows 고정/—//월 and retainer/commission notes.
Validated: branding ₩9.0M, ads ₩6.0M/월; no regression (SEO 25.0M, coaching 1.57M).

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

custom-skills/96-ourdigital-estimate-engine/SKILL.md

@@ -12,7 +12,9 @@ catalog and renders the 견적.
 ## Costing methods (catalog entry declares its `method`)
 - **effort** — `role_rate × 청구율(0.70) × 표준 업무시간`, by module; auto-tier (smb/basic/treatment)
   by portfolio size + premium-vertical floor; On-page hours scale by sub-brands (cap ×2.0);
-  제안가 = 합계 절사. Reproduces real SEO quotes (basic ₩10.5M / treatment ₩25.0M).
+  제안가 = 합계 절사. Also supports **fixed-amount tasks** (`fixed:` Unit Cost — e.g. branding
+  진단 stages) and **monthly retainers** (`unit: monthly` — e.g. ads 대행). Reproduces real
+  SEO (10.5M/25.0M), branding (₩9.0M), ads (₩6.0M/월).
 - **coaching** — `Σ(lesson_type_price × hours)` over a lesson plan; student discount opt-in.
   Reproduces real GA4/GTM 코칭 (₩1,570,000). Base prices default; subject×level matrix optional.
 - **procurement** — `unit_cost × qty × (1 + 0.15)` for non-labor items.
@@ -20,8 +22,10 @@ catalog and renders the 견적.
 ## Files
 - `references/rate_card.yaml` — universal: role rates, billing, basis, terms, tiering, scaling,
   procurement, coaching prices/levels/discounts, tools. **Private.**
-- `catalog/<service>.yaml` — per-service: `service`, `method`, body. Real: `seo` (effort),
-  `education` (coaching). Stubs: `digital_ads`, `digital_branding` (effort — `_stub: true`).
+- `catalog/<service>.yaml` — per-service: `service`, `method`, body. All real:
+  `seo` (effort, role-hours tiers), `education` (coaching, incl. GA4/GTM course),
+  `digital_branding` (effort, fixed 진단 stages → ₩9.0M), `digital_ads` (effort, ₩6.0M/월
+  retainer; media commission % is per-deal, not in catalog).
 - `scripts/estimate.py` — CLI dispatcher; `scripts/methods/{effort,coaching,procurement}.py`;
   `scripts/render.py` (md/xlsx/json). `scope.schema.json` — input contract.
 
@@ -46,8 +50,8 @@ Example consumer: `ourdigital-presales-seo` (`findings_to_scope.py` → engine
 
 ## Adding / editing services
 - New real service: add `catalog/<service>.yaml` with `method` + body from a **real quote**.
-- Stubs (`digital_ads`, `digital_branding`) carry `_stub: true` and placeholder hours — replace
-  with real quote data before client use (the 견적 prints a ⚠STUB banner).
+- Any new stub should carry `_stub: true` (the 견적 prints a ⚠STUB banner) until replaced with
+  real quote data. All current catalogs are real.
 - Rates change in `rate_card.yaml` only (single source). Validate against a known real quote.
 
 ## Conventions