git log 73cd3d8163a38532663ff9ba8643705f387ab78b...b3d7ed530aaf83e5a6decfdf391490fc74158d8d --oneline

• b3d7ed530aa Switch API test @AwaitsFix to broader issue
• f032faef25b Adds the _cluster object to the AsyncStatusResponse XContent when Clusters has a non-zero count total (#96535)
• ec6b7900a91 Migrate some uses of Version.luceneVersion() to IndexVersion (#96300)
• 8b628517a9c Load synonyms from system index for analyzers (#96674)
• 946ffa3aac1 Do not double close in AbstractHttpServerTransportTests.testForceClosesOpenChannels (#96635)
• 235133d7e1f Prune changelogs after 8.8.1 release
• 9fe1b628a7b Bump versions after 8.8.1 release
• 763cd149fcc Improve brute force vector search speed by using Lucene functions (#96617)
• 85d5a32a640 Rename service that upgrades system index mappings (#96675)
• 88419af5c0f fix incorrect definition of target (#96707)
• 60acb88cc16 Assert primary indexing requires started shard (#96704)
• d471146b66b Enhance ILM Health Indicator (#96092)
• bcd25c88881 [Fleet] Add File Delivery index templates (#96504)
• c19d7a85079 Remove the "coming" note (#96701)
• 4dbf7a7817a Mark disk usage API internal (#96692)
• df8dbdd1f1a [Main][DOCS] Add release notes for 8.8.1 release (#96590) (#96676)
• b12fa23bbcb CancellableFanOut avoiding transport threads (#96694)
• a5724ac9f4c Test rate aggregation on counters (#96472)
• 4fa7a94b2ff Add risk_score indexes for kibana_system_user (#96348)
• d1d7aea7209 Bump minimum targetCompatibility of java version checker to 1.8
• 3a4512a53d3 Fix CancellableFanOutTests#testConcurrency (#96690)
• ** e4a72bca5b4 Fix iteration of empty percentiles throwing Null Pointer Exception (#96668) **
• 92df5ac771d fast_refresh setting for stateless (#96660)
• 3c957356ef0 [Doc] Add doc pages for cross-cluter API key APIs (#96415)
• ed7e1ea6570 Add method for registering a SettingsProvider for keystore settings (#96679)
• d139a9f1064 Removing the ServlerlessScope for legacy template APIs (#96664)
• 376ff6f04d9 Merge CrossClusterAccess user into SystemUser (#96468)
• 0408f26ce8b Mute GetDataStreamsTransportActionTests#testGetTimeSeriesMixedDataStream test (#96673)
• e13091d8131 The get data stream api incorrectly prints warning log for upgraded tsdb data streams (#96606)