Merge PR #66524 into wip-pdonnell-testing-20260324.143716

* refs/pull/66524/head:
	docs: reorder mon and mds for future new releases
	doc: Check redmine-upkeep.yml to add umbrella.
	script/ceph-release-notes: add umbrella
	osd: Remove unused osd_perf_counter "scrbcnt_write_blocked"
	qa: qa tasks from the release checklist for Umbrella
	include: Remove incorrect "available" comment for feature bit. (cleanup)
	qa: add X-1 release (tentacle) to fs upgrade suite
	qa: remove reef code from fs
	osd: Remove octopus-depending code in Fast EC
	osd: Update remove after squid to remove after umbrella comment
	qa Upgrade to Umbrella
	doc: Confirm DEPRECATED checklist item and clean up pg_scrubber
	qa: update require-osd-release to umbrella
	tools/monmaptool: bump new cluster version to X
	osd/OSDMap: update to umbrella
	qa/workunits/cephtool/test: update to umbrella
	mon/OSDMonitor: update to umbrella
	common/options/global.yaml.in: update for umbrella
	mon/MgrMonitor: update for umbrella
	qa/standalone/mon/misc: update for umbrella
	doc: update compatset for umbrella
	include/ceph_features: add SERVER_UMBRELLA feature bit
	cephadm,ceph-volume: update to umbrella
	doc/dev/release-checklist: add backport-create-issue
	*: add constants and release names
	ceph_release: update to umbrella
	librbd: bump version
	CMakeLists.txt: update VERSION
	doc: reset for umbrella