During sstable summary parsing, the entire header was read into a single
buffer upfront and then parsed to obtain the positions. If the header
was too large, it could trigger oversized allocation warnings.
This commit updates the parse method to read one position at a time from
the input stream instead of reading the entire header at once. Since
`random_access_reader` already maintains an internal buffer of 128 KB,
there is no need to pre read the entire header upfront.
Fixes#24428Fixes#27590
Signed-off-by: Lakshmi Narayanan Sreethar <lakshmi.sreethar@scylladb.com>
Closesscylladb/scylladb#26846
(cherry picked from commit 3eba90041f)
Closesscylladb/scylladb#27638