Fix grants for former owners after owner change

[iBarBuba]

Summary

• Fix ACL diffing so object owners are filtered per side instead of globally across FROM and TO owners.
• Preserve explicit TO grants for a former owner after ownership changes
• Update grant comparison for schemas, tables, sequences, views, foreign tables, routines, types, and column ACLs to pass side-specific owner context.

Root cause

diff_acls previously removed FROM and TO owners from the merged grantee set. When ownership changed, this incorrectly suppressed explicit grants to the former owner in the TO database.

Closes #173

[Copilot]

Pull request overview

This PR fixes grant/ACL diffing when object ownership changes by filtering implicit-owner grantees per side (FROM vs TO) rather than removing both owners globally, ensuring explicit TO grants for a former owner are preserved.

Changes:

• Update ACL diffing to accept from_owners and to_owners and skip owner grantees only on the side where they are owners.
• Thread side-specific owner context through grant generation in Comparer::compare_grants for multiple object types (schemas, relations, routines, types, columns).
• Add regression tests covering explicit grants to a former owner after ownership changes.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
app/src/dump/acl.rs	Adds side-specific owner filtering to ACL diffing and extends unit tests for former-owner grants.
app/src/comparer/core.rs	Passes from_owners/to_owners into grant generation across object types.
app/src/comparer/core_tests.rs	Adds an integration-style regression test reproducing issue #173 behavior.

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.

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[nettrash]

Bug is real.
Fix is correct.