refactor: clean up test_acid.cc — remove unused code and deduplicate init functions

[zhanglei1949]

Summary

Clean up tests/transaction/test_acid.cc:

• Remove #include "neug/config.h" (unused)
• Remove unused using declarations: EdgeStrategy, MemoryLevel, DataTypeId, Schema
• Replace explicit UpdateTransaction type with auto
• Simplify txn.Commit() assertion (inline instead of temp variable)
• Deduplicate G1AInit/G1BInit/G1CInit/IMPInit into a single InitPersonWithVersion(db, dir, threads, initial_version)
• Remove FRInit/FR1/FR2 wrappers that just forwarded to OTV equivalents
• Add trailing newline to file

Motivation

These are pure refactoring changes extracted from the COW transaction work (PR #370) to keep that PR focused on new functionality. This cleanup reduces code duplication (~110 lines removed) and improves test readability.