refactor: move debug impls into owner packages

[peter-jerry-ye]

Motivation

Currently debug imports everything, even those immut containers, which makes it easy to create dependency cycle (see #3309 (comment))

Summary

• move package-owned Debug impls and related tests out of debug into their owner packages
• add deprecated explicit Type::to_repr methods for the moved named types so callers migrate to to_repr(x)
• trim debug package dependencies and update affected imports and debug call sites

Testing

• moon check
• moon info
• moon fmt
• moon test

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[coveralls]

Pull Request Test Coverage Report for Build 3095

Details

• 327 of 328 (99.7%) changed or added relevant lines in 20 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.02%) to 95.734%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
bytes/internal/regex_engine/ast/pattern.mbt	0	1	0.0%

Totals
Change from base Build 3090:	0.02%
Covered Lines:	13780
Relevant Lines:	14394

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💛 - Coveralls

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