v25.2.8

Features

• Introduce new "sasl_mechanisms_override" configuration that allows per-listener controls over the sasl mechanisms. by @IoannisRP in #27833

Bug Fixes

• Fixes handling batch sequence number overflow by @mmaslankaprv in #27858
• Prevent oversized allocations when table metadata gets large by @rockwotj in #27892
• Prevent oversized allocations when the kafka logger is at trace level by @rockwotj in #27815
• #27884 Schema Registry: Fix a crash during shutdown by @BenPope in #27886
• fixes possible race condition in aborting all transactions by @joe-redpanda in #27763

Improvements

• Simplified partition balancer disk usage limits by consolidating soft and hard thresholds into a single configurable setting. storage_space_alert_free_threshold_percent is no longer used for partition balancer decisions. by @bharathv in #27862
• Stabilizes DisablingPartitionsTest by @joe-redpanda in #27780
• PR #27836 [v25.2.x] k/group: replaced use of std::vector with chunked_vector by @mmaslankaprv
• PR #27854 [v25.2.x] kafka/server: keep const ref alive on the stack in futurized function by @rockwotj
• PR #27880 [v25.2.x] c/tx: fix begin of transactions without a fence batch by @bharathv
• PR #27889 [v25.2.x] [CORE-13370] archival: Fence spillover command by @Lazin
• PR #27896 [v25.2.x] iceberg: json schema: accept more chars in date-time format by @nvartolomei
• PR #27908 [v25.2.x] [CORE-13754] Make disk_log_impl::adjacent_merge_compact() pass by value (MANUAL BACKPORT) by @WillemKauf
• PR #27924 [v25.2.x] c/producer_state: fix missing placeholder in log line by @bharathv

Full Changelog: v25.2.7...v25.2.8