Add corporate and senator fun styles

Introduce two new fun styles “Corporate Bullshit” and
“Senator John Kennedy” with corresponding prompt modifiers.

Update tests to cover the new styles and verify the fun category
now contains seven entries.

Add AGENTS.md documenting repository agents
and update package-lock with optional @emnapi core and runtime dev
dependencies.

AGENTS.md

@@ -0,0 +1,27 @@
+# AGENTS.md
+
+Short map. Read only what task needs.
+
+## Core
+- App: SvelteKit + TypeScript + Vitest.
+- Keep changes small. Match existing style. No extra deps unless needed.
+- Prefer repo docs over guessing.
+
+## Read on demand
+- Product / setup: `README.md`
+- Design: `docs/superpowers/specs/2025-04-12-english-style-converter-design.md`
+- Build plan: `docs/superpowers/plans/2025-04-12-english-style-converter.md`
+- Style data: `src/lib/styles.ts`
+- LLM + prompts: `src/lib/llm.ts`
+- API: `src/routes/api/convert/+server.ts`
+- UI: `src/routes/+page.svelte`
+- Shared types: `src/lib/types.ts`
+- Component UI bits: `src/lib/components/*`
+
+## Tests
+- Use existing `npm test` / `npm run check`.
+- Add or update tests near touched code.
+
+## Notes
+- Server-only secrets stay in env vars.
+- Do not leak private prompt / defense details into UI.