Implement WhatsApp share intake and person quick actions

docs/SETUP.md

@@ -75,6 +75,32 @@ Behavior notes:
   permission prompts
 - tapping a reminder notification opens reminder management UI in-app
 
+## WhatsApp Share Intake (MVP)
+
+Inbound WhatsApp share-intake is now wired behind a listener in the authenticated
+app shell.
+
+Control flag:
+
+```bash
+flutter run --dart-define=ENABLE_WHATSAPP_SHARE_INTAKE=true
+```
+
+Disable explicitly:
+
+```bash
+flutter run --dart-define=ENABLE_WHATSAPP_SHARE_INTAKE=false
+```
+
+Behavior notes:
+
+- iOS/Android: integrates with share-intent plugin (`receive_sharing_intent`)
+- shared text is parsed and ingested into:
+  - person profile (auto-create when unresolved)
+  - source->profile link map for follow-up matching
+  - moment history (`type=whatsapp`)
+- Settings includes `Simulate WhatsApp Share` action for local/dev testing.
+
 ## Local Persistence Backend
 
 Default local store: