feat(marketing-plan): add budget, growth-patterns, and team-and-agency-model reference docs

Three new substantive frameworks integrated from Founding Marketing
(Corey Haines book) into the marketing-plan skill. Bumps
marketing-plan from 1.0.0 to 1.1.0.

New reference files:

- references/budget-planning.md (168 lines) — two scientific methods
  for setting the marketing budget: Method 1 Revenue-Based (5-40% of
  ARR with conservative/standard/aggressive postures) and Method 2
  Goal-Based (formula: [(New ARR / (ARPC * 12)) * CAC] / annual
  retention rate). Includes the 3-3-2-2-2 VC growth path (3x in years
  1-2, 2x in years 3-7 from $1M ARR), the 10-20% experimental buffer
  rule, blended CAC calculation (must include salaries, content,
  tools, retainers - not just paid spend), and the forecasting reality
  check (no startup under $100M ARR reliably hits monthly forecasts).

- references/growth-patterns.md (148 lines) — the real shape of SaaS
  growth. Phase identification ($0-10K, $10K-100K, $100K-1M, $1M+)
  with binding constraints per phase. Linear vs step-function vs
  layered S-curve growth patterns. Channel x Product x Market S-curve
  layering principle (start the next curve before the current one
  plateaus). Includes the "long slow SaaS ramp of death" framing and
  the case against the exponential-growth myth.

- references/team-and-agency-model.md (278 lines) — strategy
  in-house, execution outsourced principle. Three core marketing
  functions (Growth = demand engine, Product = story engine, Content
  = trust engine). pi-shaped marketer framework (vs T-shaped) with
  high-leverage skill-set combinations. Title progression (Manager
  -> Lead -> Director -> VP -> Chief) — don't inflate the first hire.
  Agency selection framework (Individual contractors / Small niche /
  Small generalist). Three-stage scaling model (Early / Growth /
  Scale) with internal-vs-external ratio guidance.

Enhanced existing files to wire in the new frameworks:

- SKILL.md (244 -> 270 lines) — new sections "Setting the budget
  scientifically," "Growth patterns," "Team and agency model" with
  pointers to the new reference docs. Expanded "What every plan must
  customize" from 7 items to 9 (added unit economics + phase of
  growth). Description still 949 chars (under 1024).

- references/funding-stage-unlocks.md — Related docs pointer block.

- references/measurement-framework.md — Related docs pointer block,
  new "Anchoring against the VC growth path" section, new
  "Forecasting reality check" section.

- references/methodology.md — Intake 5 (Team) now probes for
  pi-shaped vs T-shaped vs tactical-only marketing owner. Intake 6
  (Budget) now probes for blended CAC, ARPC, retention rate.

- references/plan-template.md — Section 3 adds Phase of SaaS Growth.
  Section 8 adds required unit economics table. Section 10 adds
  budget-method framing block at top + per-quarter S-curve position
  field. Section 11 adds RACI table mapping the three core functions
  to internal-owner and external-executor.

Total new content: ~600 lines across three new reference docs plus
~120 lines of integration edits. SKILL.md remains well under the
500-line convention (270).

Validates: 43/43 skills pass validate-skills.sh.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

skills/marketing-plan/references/methodology.md

@@ -137,11 +137,14 @@ For every gap in the materials, ask the user. The minimum intake covers ten topi
 - Advisors who touch marketing?
 - Agencies / contractors / fractionals?
 - Where are the obvious gaps?
+- For the team's current marketing owner (if there is one): is the shape π-shaped (two deep skill sets), T-shaped (one deep, broad), or tactical-only? See `team-and-agency-model.md` for the framework that informs Section 11 RACI and the first-hire recommendation in Section 9.
 
 #### Intake 6 — Budget
 - Current monthly marketing spend, broken down: paid acquisition, tools, retainers, headcount?
 - Budget tier this maps to (see `funding-stage-unlocks.md`)?
 - What budget unlocks when the next round closes?
+- Blended CAC if known (including salaries, content costs, tools, retainers — not just paid ad spend). If unknown, flag as the top Section 13 open decision — every revenue projection depends on it.
+- ARPC, annual retention rate (or churn rate), so the budget math in `budget-planning.md` can be applied to Section 8 (Revenue) and Section 10 (12-month outlook).
 
 #### Intake 7 — Channels currently active
 - Acquisition: organic SEO, paid search, paid social, content, social, partnerships, events, PR, ambassadors, etc. — for each, status (live / paused / never tried)