feat: @uncaged/pulse core engine — runPulse + Rule type + S combinator composition

- Moore machine model: Effects determined by state diff, not events
- S combinator rule composition: pulse = S r3 . S r2 . S r1 $ dummy
- createRule helper with accessor-based state adaptation
- 7 tests passing (compose, async, adaptive tickMs, Moore property)

Design: https://github.com/oc-xiaoju/ograph/issues/44

docs/DESIGN.md

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+# Design Document
+
+See [RFC #44: Pulse — Agent 的自主神经系统](https://github.com/oc-xiaoju/ograph/issues/44)
+
+## Summary
+
+### Core Formula
+
+```
+f(prevSnapshot, currSnapshot) → (Effect[], tickMs)
+```
+
+### Key Properties
+
+- **Moore Machine** — Effects determined by state, not events. Pulse polls projection values, not event streams.
+- **Path Dependent** — Sampling is lossy. A→B + B→C ≠ A→C at the effect level. Poll frequency = resolution of reality.
+- **S Combinator** — Single composition primitive. `pulse = S r3 . S r2 . S r1 $ dummy`
+- **Not Forced Pure** — Rules can be async/impure. Framework doesn't distinguish certain/uncertain.
+- **Agent Managed** — The rule repo is managed by the Agent. Types, rules, collectors, effectors — all TypeScript, all under `tsc` guard.
+- **Staging via git worktree** — Safe experimentation before promote to production.
+
+### Packages
+
+| Package | Purpose |
+|---------|---------|
+| `@uncaged/pulse` | Core engine: `runPulse()` + `Rule` type. Generic, zero deps. |
+| `@uncaged/upulse` | CLI: daemon lifecycle + test/staging/promote |
+| `@uncaged/pulse-rules` | Shared rule library (future) |