(DOC+) Node Stats fs.available reflects XFS quotas (#106085)

Moving https://github.com/elastic/elasticsearch/pull/103472 here.

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👋 howdy, team!

Could we include "XFS quotas" as an example for "depending on OS or process level restrictions" for this doc's searchability for users to better understand how to investigate this potential lever's impact?

TIA!

docs/reference/cluster/nodes-stats.asciidoc

@@ -1792,14 +1792,14 @@ Total number of unallocated bytes in all file stores.
 `available`::
 (<<byte-units,byte value>>)
 Total disk space available to this Java virtual machine on all file
-stores. Depending on OS or process level restrictions, this might appear
+stores. Depending on OS or process level restrictions (e.g. XFS quotas), this might appear
 less than `free`. This is the actual amount of free disk
 space the {es} node can utilise.
 
 `available_in_bytes`::
 (integer)
 Total number of bytes available to this Java virtual machine on all file
-stores. Depending on OS or process level restrictions, this might appear
+stores. Depending on OS or process level restrictions (e.g. XFS quotas), this might appear
 less than `free_in_bytes`. This is the actual amount of free disk
 space the {es} node can utilise.
 =======