feat: prevent wildcard deletion in deleteUser/deleteRole APIs

[Copilot]

Fix deleteUser() deleting all policies when called with empty string

Root Cause

The enforcer.deleteUser() method does not validate the user parameter. When called with an empty string '', it causes all policies to be deleted because empty string values are treated as wildcards in removeFilteredPolicy. This results in SQL queries like:

DELETE FROM casbin_rule WHERE ptype = 'p';
DELETE FROM casbin_rule WHERE ptype = 'g';

Changes Made

• Identify root cause: empty string parameter acts as wildcard
• Add validation to deleteUser() to reject empty/falsy user values
• Add validation to deleteRole() which has the same issue
• Add validation to deletePermission() and other similar methods
  • deleteRoleForUser() - validates both user and role
  • deleteRolesForUser() - validates user
  • deletePermissionsForUser() - validates user
  • deletePermissionForUser() - validates user
  • deletePermission() - validates permission array is not empty
• Add tests to verify empty string handling (7 new tests)
• Run existing tests to ensure no regressions (all 190 tests pass)
• Fix linting issues
• Request code review (no issues found)
• Run security scan (no vulnerabilities found)
• Revert yarn.lock to original state

Security Summary

No security vulnerabilities were found in the changes. The fix actually improves security by preventing accidental data loss when invalid parameters are provided.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>enforcer.deleteUser() wiped out all data from casbin_rule table</issue_title>
<issue_description>Logged queries shows that following queries are executed when calling enforcer.deleteUser()

DELETE from casbin_rule WHERE ptype = 'p';
DELETE from casbin_rule WHERE ptype = 'g'; 
```</issue_description>

## Comments on the Issue (you are @copilot in this section)

<comments>
</comments>

• Fixes enforcer.deleteUser() wiped out all data from casbin_rule table #462

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[hsluoyz]

@copilot don't modify yarn.lock

[Copilot]

@copilot don't modify yarn.lock

Reverted yarn.lock to its original state in commit 5599e1a.

[coveralls]

Pull Request Test Coverage Report for Build 20874840964

Details

• 16 of 16 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.2%) to 78.472%

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Totals
Change from base Build 20679550322:	0.2%
Covered Lines:	1661
Relevant Lines:	2017

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💛 - Coveralls