Pinecone change history: [GCP][europe-west4] Errors for upsert operations on some indexes

Pinecone reported a major incident causing upsert errors on some indexes in GCP europe-west4, affecting Serverless Indexes. It started at 2026-03-13 08:50 UTC and was resolved at 2026-03-13 09:53 UTC, lasting 1 h 3 min; a fix was implemented and monitored before resolution.