[WIP] Refactor luaopen_re to luaopen_lpeg_re

[Copilot]

• Rename luaopen_re to luaopen_lpeg_re in generated code
• Update main.c to register the module as 'lpeg.re' instead of 're'
• Update luvi.h to declare luaopen_lpeg_re instead of luaopen_re
• Modify luac.lua to generate proper function names for submodules
• Add unit tests for both require('lpeg.re') and require('lpeg')
• Test the changes with both build configurations
• Ensure backward compatibility is considered

Original prompt

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This section details on the original issue you should resolve

<issue_title>refactor luaopen_re to luaopen_lpeg_re</issue_title>
<issue_description>In #307, we introduce luaopen_re, support require('re') to imporet RE module.

1. Not match require('lpeg.re')
2. only works when BUNDLE_USE_LUA2C set ON, compile fail when set OFF.
3. Without unit test.
4. Maybe cause Compilation Fails with Segmentation Fault on ARM64 (RK3568) when Building lpeg/re.lua #304

I think we need fix this. @Bilal2453 @truemedian @squeek502 </issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes refactor luaopen_re to luaopen_lpeg_re #309

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