pgsql: Consolidate replication origin session globals into a single str

Consolidate replication origin session globals into a single struct.

This commit moves the separate global variables for replication origin
state into a single ReplOriginXactState struct. This groups logically
related variables, which improves code readability and simplifies
state management (e.g., resetting the state) by handling them as a
unit.

Author: Chao Li <lic(at)highgo(dot)com>
Suggested-by: Ashutosh Bapat <ashutosh(dot)bapat(dot)oss(at)gmail(dot)com>
Reviewed-by: Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com>
Reviewed-by: Ashutosh Bapat <ashutosh(dot)bapat(dot)oss(at)gmail(dot)com>
Discussion: https://postgr.es/m/CAEoWx2=pYvfRthXHTzSrOsf5_FfyY4zJyK4zV2v4W=yjUij1cA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8f1e2dfe033e9a3236265c3b9f61bd226f4a8f54

Modified Files
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src/backend/access/transam/twophase.c | 32 +++++++++----------
src/backend/access/transam/xact.c | 36 +++++++++++-----------
src/backend/access/transam/xloginsert.c | 6 ++--
.../replication/logical/applyparallelworker.c | 6 ++--
src/backend/replication/logical/origin.c | 26 ++++++++--------
src/backend/replication/logical/tablesync.c | 4 +--
src/backend/replication/logical/worker.c | 28 ++++++++---------
src/include/replication/origin.h | 11 +++++--
src/tools/pgindent/typedefs.list | 1 +
9 files changed, 79 insertions(+), 71 deletions(-)