docs(lock): clarify ILockManager API documentation

[joshtrichards]

Summary

Improve the ILockManager documentation and also fix a presumed bug in the underlying registerLockProvider() implementation.

Changes

• improve the interface-level description for ILockManager
• document registerLazyLockProvider() throwing PreConditionNotMetException when a provider is already registered
• document runInScope() throwing PreConditionNotMetException when a scope is already active
• fix getLockInScope() docs to reflect that it returns null when no scope is active instead of throwing
• clarify that isLockProviderAvailable() checks current availability and may attempt lazy provider resolution
• Implementation fix: align registerLockProvider() behavior with the documented single-provider registration contract by also rejecting previously registered lazy providers

Notes

This change is intended to improve API clarity and keep the public interface documentation in sync with the implementation. No functional behavior changes are intended beyond the consistency fix in registerLockProvider().

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)
• Labels added where applicable (ex: bug/enhancement, 3. to review, feature component)
• Milestone added for target branch/version (ex: 32.x for stable32)

AI (if applicable)

• The content of this PR was partly or fully generated using AI