[php-*] Fix indention of PHP documentation

[coffeemakr]

Adjust the indention in the php comments.

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Summary by cubic

Fix PHPDoc indentation in generated PHP code across php-nextgen, php-symfony, and legacy php templates. This cleans up docblocks, aligns with PHPDoc/PSR-12 style, and avoids tooling warnings without changing runtime behavior.

• Bug Fixes
  • Aligned leading asterisks and tags in docblocks (methods, enums, models, Symfony serializer annotations); added missing docblock starts where needed.
  • Regenerated PHP samples to reflect the formatting updates.

^{Written for commit 65fe0e9. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 182 files

Note: This PR contains a large number of files. cubic only reviews up to 75 files per PR, so some files may not have been reviewed.

[coffeemakr]

CC php members: @jebentier @dkarlovi @mandrean @jfastnacht @ybelenko @renepardon