chore(release): v1.8.2 — one intake row per dose slot

Guarantees a single intake entry per scheduled dose: intake writes snap
to the canonical slot instant and update in place rather than inserting a
sibling row, a re-sync can no longer clear a recorded dose, concurrent
logs converge, and a one-time startup pass collapses existing duplicates.

docs/api/openapi.yaml

@@ -1,7 +1,7 @@
 openapi: 3.1.0
 info:
   title: HealthLog API
-  version: 1.8.1
+  version: 1.8.2
   description: >-
     Self-hosted personal-health-tracking PWA — public API surface for the iOS native client and external ingest.