refactor(plugins)!: standardize shared-library names

[nick2781]

Official, server and sample plugin targets now emit lowercase snake_case shared libraries, for example ark_mysql_plugin, ark_utility_plugin and sample1_plugin. Update the application manifests, embedded deployment configuration and current bilingual documentation together so the loader continues to find the generated files. Platform extensions and the Debug _d suffix are preserved; exported entry-point names are unchanged.

Add CMake validation and a repository policy regression to keep new declarations consistent. Historical documentation archives remain byte-identical.

Validation:

• Built the real launcher, utility plugin and Sample1; both ordinary and Debug variants loaded the renamed libraries and completed startup, SIGTERM shutdown and module shutdown hooks with exit 0.
• Core tests: 48 cases / 2,546 assertions passed, including updated manifest parsing expectations.
• All 71 CI policy tests, clang-format 18, whitespace checks, and the complete Nimbus check passed (123 HTML pages / 217 internal references).

Native Windows/Linux artifact loading was not performed locally; required CI remains pending.

BREAKING CHANGE: replace legacy AF*Plugin and Sample*Plugin build targets and configured library stems with their snake_case names. Old shared-library filenames are no longer generated. Existing external plugins and the exported plugin ABI entry-point names are not renamed by this change.