chore: refine custom array type fix

[tianzhou]

Refine the fix in #163

[Copilot]

Pull Request Overview

This PR refines the handling of custom array types by moving type resolution from Go-based string manipulation to SQL query-level logic. Instead of post-processing type names with a _ prefix, the system now detects and resolves array types directly in PostgreSQL queries by inspecting the element type relationship.

• Removed Go code that converted internal PostgreSQL array notation (e.g., _my_enum_type) to standard array syntax
• Enhanced SQL queries to detect array types and resolve their element type schemas at query time
• Updated test data to verify proper handling of custom enum array columns

Reviewed Changes

Copilot reviewed 15 out of 15 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
ir/normalize.go	Removed obsolete custom array type string manipulation logic
ir/queries/queries.sql	Added array type detection and element type resolution for both GetColumns and GetColumnsForSchema queries
ir/queries/queries.sql.go	Generated code corresponding to the SQL query changes
testdata/diff/create_table/enum_array_column/*	Removed old test data files
testdata/diff/create_table/add_column_array/*	Updated test data to include enum array type column with version bump to 1.4.1

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[Copilot]

Pull Request Overview

Copilot reviewed 15 out of 15 changed files in this pull request and generated no new comments.

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