v26.7.0

Notes The Nimbus consensus client v26.7.0 is a medium-urgency release which optimizes CPU and memory usage. Improvements Implements backfilled column reconstruction: #8533 Reply with correct error message in block req/resp for unavailable blocks: #8719 Reassemble only custodied columns from execution client mempool: #8672 Fixes Prevents libp2p pubsub peer leakage: #8699 #8701 Prune colunm…