WL#17237: Make "GR: Up-to-date Aware Primary Election on Failover" community edition

# EXECUTIVE SUMMARY

This worklog makes the existing `GR: Up-to-date Aware Primary Election on
Failover` available in the MySQL Community Edition.

This change will enable the DBA to influence the primary member on failover in
single-primary mode by also taking replication member most up-to-date into
account. The change aligns feature availability between Community and
Enterprise editions without introducing new functionality or altering existing
behavior.


# USER STORIES

* As a MySQL Community Edition admin, I want to configure MySQL Group
  Replication, when in single-primary mode, to elect the secondary most
  up-to-date on failover.

* As a MySQL Community Edition customer I want the system to honor the preferred
  placement expressed via the REST API, even if the secondary chosen is the one
  with higher lag so that I keep my whole stack together (same AD).

# FUNCTIONAL REQUIREMENTS

FR-01. The `GR: Up-to-date Aware Primary Election` feature shall be
       available in the MySQL Community Edition build.

FR-02. The feature shall expose the same `Up-to-date Aware Primary Election` in
       the Community Edition as currently available in the Enterprise Edition.

FR-03. The feature shall be available in Community Edition builds, consistent
       with current behavior in Enterprise Edition builds.

FR-04. Existing interfaces (e.g., performance schema tables, status variables,
       or instrumentation points) used to expose the stats shall remain
       unchanged.

FR-05. The change shall be transparent to users upgrading from earlier versions,
       with no configuration changes required.

FR-06. There shall be no functional regressions or behavior changes to group
       replication, or performance when the feature is enabled.

FR-07. The implementation shall maintain compatibility across supported
       platforms for Community Edition builds.

# NON-FUNCTIONAL REQUIREMENTS

NFR-01. Logging, error handling, and diagnostics behavior shall remain
        unchanged.

# Summary of the approach

This worklog makes the existing `GR: Up-to-date Aware Primary Election on
Failover` available in the MySQL Community Edition.

This change will enable the DBA to influence the primary member on failover in
single-primary mode by also taking replication member most up-to-date into
account. The change aligns feature availability between Community and
Enterprise editions without introducing new functionality or altering existing
behavior.

No changes are made to group replication logic, metrics collection, or
exposure mechanisms.

# Security context

No applicable changes on security context.

# Observability

Observability remains unchanged.

# Upgrade/downgrade and cross-version replication

Upgrades from earlier Community Edition versions will automatically gain access
to the Group Replication `Up-to-date Aware Primary Election`, without
requiring configuration changes.

Downgrades behave as before; feature not supported by the downgraded version
will simply be unavailable.

Cross-version replication behavior is unchanged.

There is no impact on group replication compatibility between Community and
Enterprise Edition instances.

# User interface

No new user interfaces are introduced.

Existing SQL interfaces, system tables, and performance schema views remain
unchanged.

Users interact with the feature using the same queries and tools as before.

# Deployment and installation

The change affects build and packaging only.

Community Edition binaries will include the feature by default.

No special installation steps are required.

Deployment workflows remain unchanged.

# Protocol

No protocol changes.

# Failure Model Specification

No new failure modes are introduced.

# Behavior Changes

The only behavior change is the availability of Group Replication `Up-to-date
Aware Primary Election` feature in Community Edition.

There are no changes to group replication behavior, stats semantics, or
default configurations.

Enterprise Edition behavior remains unchanged.