feat(iam): add SetUserStatus and UpdateAccessKey actions (#7745)
Add ability to enable/disable users and access keys without deleting them.
## Changes
### Protocol Buffer Updates
- Add `disabled` field (bool) to Identity message for user status
- false (default) = enabled, true = disabled
- No backward compatibility hack needed since zero value is correct
- Add `status` field (string: Active/Inactive) to Credential message
### New IAM Actions
- SetUserStatus: Enable or disable a user (requires admin)
- UpdateAccessKey: Change access key status (self-service or admin)
### Behavior
- Disabled users: All API requests return AccessDenied
- Inactive access keys: Signature validation fails
- Status check happens early in auth flow for performance
- Backward compatible: existing configs default to enabled (disabled=false)
### Use Cases
1. Temporary suspension: Disable user access during investigation
2. Key rotation: Deactivate old key before deletion
3. Offboarding: Disable rather than delete for audit purposes
4. Emergency response: Quickly disable compromised credentials
Fixes#7745
* move s3account.AccountManager into to iam.S3ApiConfiguration and switch to Interface
https://github.com/seaweedfs/seaweedfs/issues/4519
* fix: test bucket acl default and
adjust the variable names
* fix: s3 api config test
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Co-authored-by: Konstantin Lebedev <9497591+kmlebedev@users.noreply.github.co>
Co-authored-by: Chris Lu <chrislusf@users.noreply.github.com>