[API] Extend Mirror API with Architecture Configuration

common_properties = {
    # ... existing properties ...

    "architecture_filter": {
        "type": ["array", "null"],
        "description": "List of architectures to mirror. Empty or null mirrors all architectures.",
        "items": {
            "type": "string",
            "enum": ["amd64", "arm64", "ppc64le", "s390x", "386", "riscv64"]
        },
        "uniqueItems": True,
        "example": ["amd64", "arm64"]
    },
}

@require_repo_read(allow_for_superuser=True)
@define_json_response("RepoMirrorConfig")
def get(self, namespace_name, repository_name):
    """Get repository mirror configuration."""
    mirror = model.repo_mirror.get_mirror(repository)

    if mirror is None:
        raise NotFound()

    return {
        # ... existing fields ...
        "architecture_filter": mirror.architecture_filter or [],
    }

@require_repo_admin(allow_for_superuser=True)
@validate_json_request("RepoMirrorConfig")
def put(self, namespace_name, repository_name):
    """Update repository mirror configuration."""
    values = request.get_json()

    # ... existing validation ...

    # Handle architecture filter
    if "architecture_filter" in values:
        arch_filter = values["architecture_filter"]
        if arch_filter:
            validate_architecture_filter(arch_filter)

        model.repo_mirror.set_architecture_filter(
            repository,
            arch_filter or []
        )

        # Audit log the change
        track_and_log(
            "repo_mirror_config_changed",
            repository,
            {
                "field": "architecture_filter",
                "value": arch_filter,
            }
        )

    # ... rest of update logic ...

VALID_ARCHITECTURES = {"amd64", "arm64", "ppc64le", "s390x", "386", "riscv64"}

def validate_architecture_filter(arch_filter):
    """
    Validate architecture filter values.

    Raises:
        InvalidRequest: If any architecture value is invalid
    """
    if not isinstance(arch_filter, list):
        raise InvalidRequest("architecture_filter must be an array")

    invalid_archs = set(arch_filter) - VALID_ARCHITECTURES
    if invalid_archs:
        raise InvalidRequest(
            f"Invalid architecture values: {', '.join(sorted(invalid_archs))}. "
            f"Valid values: {', '.join(sorted(VALID_ARCHITECTURES))}"
        )

    if len(arch_filter) != len(set(arch_filter)):
        raise InvalidRequest("Duplicate architecture values not allowed")

schemas = {
    "RepoMirrorConfig": {
        "type": "object",
        "properties": {
            # ... existing properties ...
            "architecture_filter": {
                "type": "array",
                "items": {"type": "string"},
                "description": "List of architectures to mirror",
            },
        },
    },
}

{
    "is_enabled": true,
    "external_reference": "docker.io/library/nginx",
    "sync_interval": 86400,
    "robot_username": "org+robot",
    "root_rule": {
        "rule_kind": "tag_glob_csv",
        "rule_value": ["latest", "1.*"]
    },
    "architecture_filter": ["amd64", "arm64"]
}

{
    "architecture_filter": ["amd64"]
}

{
    "status": 400,
    "error_message": "Invalid architecture values: x86. Valid values: 386, amd64, arm64, ppc64le, riscv64, s390x",
    "error_type": "invalid_request"
}

# In migration or seeding
LogEntryKind.create(name="repo_mirror_architecture_changed")

track_and_log(
    "repo_mirror_config_changed",
    repository,
    {
        "field": "architecture_filter",
        "old_value": old_arch_filter,
        "new_value": new_arch_filter,
    }
)

def test_get_mirror_includes_architecture_filter():
    """Test GET response includes architecture_filter field."""

def test_get_mirror_empty_architecture_filter():
    """Test GET returns empty array when no filter configured."""

def test_put_mirror_architecture_filter():
    """Test updating mirror with architecture filter."""

def test_put_mirror_architecture_filter_validation():
    """Test invalid architecture values are rejected."""

def test_put_mirror_architecture_filter_empty():
    """Test setting empty array clears filter."""

def test_put_mirror_architecture_filter_null():
    """Test setting null clears filter."""

def test_put_mirror_architecture_filter_duplicate():
    """Test duplicate architecture values are rejected."""

def test_put_mirror_backwards_compatible():
    """Test existing clients without architecture_filter still work."""

def test_architecture_filter_audit_logged():
    """Test changes to architecture filter are logged."""