v1.32.1

Fixes the v1.32.0 known issue: cross-tenant dedupe data loss. The dedup scan is now partitioned by tenant, so byte-identical content in two tenants is never a duplicate pair and one tenant's rows can no longer be deleted because another tenant holds the same content. Survivor ordering unchanged within each tenant; single-tenant stores byte-identical. Both the sleep dedupe phase and hippo dedup inherit the fix. Gates: plan 92, code 92, codex clean r1, independent review 95, suite 2980/0, E2E acceptance drive flipped the original repro. PR #144.