chore(release): v1.28.32 — Fitbit re-keyed re-imports can no longer be silently dropped

Single-fix release mirroring the Google Health natural-key rescue from
v1.28.28 into the Fitbit sync. The measurements natural-key unique index
(user, type, measured_at, source, sleep_stage — NULLS NOT DISTINCT,
migration 0055) covers tombstoned rows, so a re-import carrying NEW
externalIds for previously-removed rows collided on the natural key and
skipDuplicates dropped the insert silently. Every planned create now gets
a second chunked probe by natural key with no deletedAt filter; a match —
live or tombstoned — is updated in place with the fresh value, the new
externalId, and deletedAt: null. Probe failure notes the hard-failure
ledger so the watermark holds and the next tick retries. No other code
path touched.

docs/api/openapi.yaml

@@ -1,7 +1,7 @@
 openapi: 3.1.0
 info:
   title: HealthLog API
-  version: 1.28.31
+  version: 1.28.32
   description: >-
     Self-hosted personal-health-tracking PWA — public API surface for the iOS native client and external ingest.