Windsurf + Aider targets, MCP server, and demo placement (#33)

Broadens both reach (more tools) and content types (an MCP server), continuing
the multi-platform story.

Windsurf + Aider:
- build-exports.mjs gains two platforms: exports/windsurf/*.md (workspace rules,
  trigger: model_decision) and exports/aider/*.md (conventions for `aider --read`).
  Now 5 platforms (ChatGPT, Gemini, Cursor, Windsurf, Aider).
- install.sh + bin/cli.mjs install both (windsurf -> .windsurf/rules, aider ->
  .aider/skills with a --read hint); generated README index is excluded from copies.
- One-line windsurf-install.sh / aider-install.sh wrappers for parity.

MCP server (new content type):
- mcp/server.mjs — zero-dependency stdio MCP server exposing list_skills,
  search_skills, get_skill. Published as a second bin (pm-claude-skills-mcp).
  Logs to stderr; reads bundled skills/ at startup. mcp/README.md documents
  client config.

Also: README hero "See it in action" demo placement (ready to swap in a GIF;
recording guide in web/docs-assets/README.md), Works-With table + exports +
install docs updated, CHANGELOG Unreleased. package.json files/bin updated.


Claude-Session: https://claude.ai/code/session_016JWn5jRD5tcEFKrubjQ6Px

Co-authored-by: Claude <noreply@anthropic.com>

exports/windsurf/pm-finance/financial-model-narrative/financial-model-narrative.md

@@ -0,0 +1,78 @@
+---
+trigger: model_decision
+description: "Turn financial model outputs into a clear written narrative. Use when asked to write a financial narrative, explain a financial model, summarise a P&L, or translate spreadsheet numbers into a board-ready story. Produces an executive narrative with key insights, drivers, and forward-looking commentary."
+---
+
+# Financial Model Narrative Skill
+
+Turns financial model outputs into a clear, structured written narrative suitable for board packs, investor updates, or management reporting.
+
+## Required Inputs
+- **Financial data** (paste key figures: revenue, costs, margins, EBITDA, cash)
+- **Period covered** (month / quarter / annual / multi-year)
+- **Audience** (board / investors / management / bank / internal)
+- **Key message** (what is the headline story?)
+- **Actuals vs budget / prior period?** (comparison context)
+
+## Output Structure
+
+### 1. Headline Summary
+3-5 sentences. The financial story in plain English. Lead with the most important insight — not "revenue was X" but what that figure means.
+
+### 2. Revenue
+- Performance vs prior period / budget
+- Key drivers: what caused the movement
+- Risks or opportunities in the revenue line
+
+### 3. Costs and Margins
+- Gross margin: % and trend
+- Key cost movements and why
+- EBITDA performance and drivers
+- One-off items clearly flagged
+
+### 4. Cash and Balance Sheet
+- Cash position and movement
+- Runway (for startups)
+- Key working capital movements
+
+### 5. Variance Analysis
+For each significant variance:
+
+**[Line item] — Over/Under by [amount]**
+- **Cause:** [Plain English explanation]
+- **Permanent or temporary?** One-time / Structural
+- **Action being taken:** [If applicable]
+
+### 6. Forward-Looking Commentary
+- Expected next period
+- Key risks to forecast
+- Key opportunities
+- Any reforecast or guidance change
+
+## Writing Rules
+- Never just restate a number — always explain what it means
+- Flag variances over 10% automatically
+- Use past tense for actuals, conditional for forecast
+- One insight per paragraph
+
+## Quality Checks
+
+- [ ] Headline summary leads with meaning, not just the number
+- [ ] Every significant variance has a cause, permanence, and action
+- [ ] Forward-looking commentary includes specific risks and opportunities
+- [ ] Audience-appropriate language (board vs investor vs management)
+- [ ] One-off items clearly distinguished from recurring items
+
+## Anti-Patterns
+
+- [ ] Do not list numbers without explaining what is driving them — narrative must go beyond restating the figures
+- [ ] Do not mix one-off items with recurring performance without clearly distinguishing them
+- [ ] Do not write the same level of detail for all line items — focus depth on the items that matter most
+- [ ] Do not omit forward-looking commentary — a narrative without outlook is incomplete for board or investor audiences
+- [ ] Do not use technical accounting language without translation — the audience is executives, not accountants
+
+## Example Trigger Phrases
+- "Write a financial narrative for these results: [paste numbers]"
+- "Turn this P&L into a board narrative"
+- "Write the finance section of our board pack"
+- "Explain these financial results in plain English"