Improve error messages for unsupported __audit database operations

[CRZbulabula]

Description

Error message

Replace the misleading read-only error used for unsupported operations on the audit database with a more accurate message:

Apache IoTDB does not support this operation on database '%s'.

The message is shared by the tree-model and table-model authorization paths and is localized in both English and Chinese.

Affected operations

• Apply the new message to tree-model write, schema, template, TTL, and database deletion checks that previously reported the audit database as read-only.
• Apply the same message to unsupported table-model operations on __audit.
• Keep the existing reserved-name, grant/revoke, and AUDIT-admin query messages unchanged because they already describe their restrictions precisely.

Test coverage

• Add coverage for DELETE DATABASE root.__audit and template operations in IoTDBTemplateAuthIT.
• Update TTL coverage in IoTDBSeriesPermissionIT.
• Add coverage for DROP DATABASE __audit in IoTDBAuthenticationTableIT.

Verified with:

• Full-reactor English and Chinese test compilation.
• IoTDBTemplateAuthIT#manageDataBaseTest.
• IoTDBSeriesPermissionIT#ttlOperationsTest.
• IoTDBAuthenticationTableIT#testInsert with the table-simple profile.

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This PR has:

• been self-reviewed.
• added comments explaining the intent where it was not obvious.
• added or updated integration tests.
• been tested in a test IoTDB cluster.

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Key changed/added classes (or packages if there are too many classes) in this PR

• AccessControlImpl
• ITableAuthCheckerImpl
• TreeAccessCheckVisitor
• DataNodeQueryMessages