refactor: simplify embeded pg

[tianzhou]

No description provided.

[Copilot]

Pull Request Overview

This PR consolidates embedded PostgreSQL functionality by moving all related code from cmd/util and ir packages into testutil, making it available for both testing and production use. The refactoring eliminates code duplication and establishes testutil as the single source of truth for embedded PostgreSQL management.

Key Changes:

• Moved embedded PostgreSQL management, version detection, and test helper functions from cmd/util and ir packages to testutil
• Updated all imports and references across the codebase to use testutil instead of cmd/util for embedded PostgreSQL functionality
• Added support for nil testing.T parameter to enable usage in production code and TestMain contexts

Reviewed Changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
testutil/postgres.go	Added comprehensive embedded PostgreSQL functionality including version detection, instance management, and test helpers
ir/testutil.go	Removed (functionality moved to testutil package)
ir/testing.go	Added convenience wrappers that delegate to testutil functions
cmd/util/postgres_version.go	Removed (functionality moved to testutil)
cmd/util/postgres_version_test.go	Removed (tests moved to testutil)
cmd/util/embedded_postgres.go	Removed (functionality moved to testutil)
cmd/util/embedded_postgres_test.go	Removed (tests moved to testutil)
cmd/util/embedded_postgres_test_helper.go	Removed (functionality moved to testutil)
cmd/plan/plan.go	Updated imports to use testutil instead of util for embedded PostgreSQL
cmd/apply/apply.go	Updated imports to use testutil instead of util for embedded PostgreSQL
cmd/migrate_integration_test.go	Updated imports and type references to use testutil
cmd/apply/apply_integration_test.go	Updated imports and type references to use testutil

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[Copilot]

Pull Request Overview

Copilot reviewed 20 out of 20 changed files in this pull request and generated 2 comments.

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[Copilot]

Pull Request Overview

Copilot reviewed 20 out of 20 changed files in this pull request and generated 4 comments.

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[Copilot]

Pull Request Overview

Copilot reviewed 20 out of 20 changed files in this pull request and generated 1 comment.

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[Copilot]

Pull Request Overview

Copilot reviewed 20 out of 20 changed files in this pull request and generated 4 comments.

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