fix: raise error when fail in public lua functions

Summarize the changes

Для публичных функций из core-router.lua в случае ошибки следует использовать error вместо return nil. Иначе lua.call_with_args не понимает, что вернулась ошибка и воспринимает nil как успех (который она не может прочитать с луа стека). В результате, вместо настоящей ошибки, пользователь видит ошибку чтения с луа стека.

Ensure that

• New code is covered by unit and integration tests.
• Related issues would be automatically closed with gitlab's closing pattern (Closes #1, #2).
• Public modules are documented (check the rendered version with cargo doc --open).
• (if PEST grammar is changed) EBNF grammar reflects these changes (check the result with railroad diagram generator.

Next steps

• Cherry-pick to: none
• Update sbroad submodule in picodata/picodata.
• (if EBNF grammar is changed) create a follow-up issue in picodata/docs.

assigned to @kusancho

marked this merge request as draft

added 17 commits

• 642719f3...7dad8474 - 16 commits from branch main
• 7f84ebc8 - fix: detailed error message from lua

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requested review from @darthunix

added 1 commit

• 534595af - fix: public lua functions should fail with error

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changed the description

added bug label

changed milestone to %24.6 - Plugins and Tiers

marked this merge request as ready

changed title from fix: detailed error message from lua to fix: raise error when fail in public lua functions

@kusancho я заленился это делать, но в идеале было бы неплохо добавить тесты для этих луа функций.

added 14 commits

• 534595af...2859cbdb - 13 commits from branch main
• ec772515 - fix: public lua functions should fail with error

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enabled an automatic merge when the pipeline for ec772515 succeeds

merged