refactor: implement self* methods using WithoutNotify pattern (sync with Go)

[Huggin423]

Description

This PR refactors the implementation to match the Go Casbin approach, as requested by the maintainer.

It introduces *WithoutNotify internal methods that operate strictly on the memory model (bypassing both adapter and watcher) and updates self* methods to call them directly. This prevents infinite loops in distributed environments.

Related Issue

Fixes #506

Verification

• Tested locally using the provided test script.
• Verified that selfAddPolicy updates memory correctly without invoking adapter.addPolicy.

[coveralls]

Pull Request Test Coverage Report for Build 20746293363

Details

• 41 of 62 (66.13%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-1.0%) to 77.263%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/internalEnforcer.ts	34	55	61.82%

Totals
Change from base Build 20679550322:	-1.0%
Covered Lines:	1682
Relevant Lines:	2053

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💛 - Coveralls