[GR-49525] Option '--future-defaults=<option>' to enable options that are planned to become defaults in future releases.

[graalvmbot]

Introduced --future-defaults=[all|run-time-initialized-jdk|none] that allows for gentle migration to the future default behaviors of Native Image. The only currently enabled option is run-time-initialized-jdk. This option shifts away from build-time initialization of the JDK, instead initializing most of it at run time. This transition is gradual, with individual components of the JDK becoming run-time initialized in each release. This process should complete with JDK 29 when this option should not be needed anymore. Unless you store classes from the JDK in the image heap, this option should not affect you. In case this option breaks your build, follow the suggestions in the error messages.

Value all includes all options.
Value none resets all previous settings and can be set only on the command line. Other options can be placed in JAR files as well.

Note: what makes it into the future-defaults must not be an experimental feature that can be rolled back. The changes must permanent and guaranteed behavior for the future.

Build Output

 Recommendations:
 G1GC: Use the G1 GC ('--gc=G1') for improved latency and throughput.
 PGO:  Use Profile-Guided Optimizations ('--pgo') for improved throughput.
 FUTR: Use '--future-defaults=all' to prepare for future releases.
 HEAP: Set max heap for improved and more predictable memory usage.
 CPU:  Enable more CPU features with '-march=native' for improved performance.

[jerboaa]

@vjovanov Could you please add a description to this PR? It shows up empty over here :-/