Record UX guidance delivery PR (#10)

docs/implementation.md

@@ -3,6 +3,7 @@
 ## Reusable UX guidance — task #10
 
 [Task #10](https://git.sendico.io/tech/sxchnge/issues/10), branch `skills-10`,
+delivered in [PR #11](https://git.sendico.io/tech/sxchnge/pulls/11) into `main`,
 adds a concise root UX policy linking two independent skills in `skills/`:
 UX Design covers usable interfaces and its design review; UX Observability covers
 purposeful journey measurement and its observability review. Both preserve product