feat(local): model local command log boundary

Define local/offline truth as commands, domain events, and projections rather than stored DOM patches or EffectBatch payloads, and wire the techdemo through a local command-to-projection-to-effect flow.

req: local/001

req: local/002

req: local/003

req: local/004

req: examples/001

REQUIREMENTS.md

@@ -572,6 +572,22 @@ what a valid business email is.
 
 ---
 
+## local
+
+### req: local/001
+001	Local/offline behavior is represented as app commands, domain events, and projections. Stored DOM patches or stored EffectBatch payloads are not the source of truth.
+
+### req: local/002
+002	Local command logs are app or integration territory until a reusable hemx contract proves common semantics across multiple apps. hemx core must not gain a mandatory browser database, client store, sync engine, or conflict policy.
+
+### req: local/003
+003	Replaying local work back to a server or peer sync target is explicit app/integration policy. A local projection may render immediate feedback, but server acceptance, rejection, reconciliation, export, and deletion rules remain visible product decisions.
+
+### req: local/004
+004	A local-first exemplar must show a command becoming a domain event and projection before hemx UI effects are produced, so the UI effect remains output of app state rather than persisted truth.
+
+---
+
 ## interop
 
 ### req: interop/001