Support self-serve Business ProLite accounts (#35785)

## What changed

- Recognize `self_serve_business_prolite` across authentication, account and rate-limit APIs, generated schemas, workspace classification, status display, cloud configuration gating, and usage-limit messaging.
- Keep the Python SDK's `PlanType` enum compatible with non-empty string values introduced by newer Codex runtimes while preserving its known constants.

## Testing

- Cover token parsing, account reads and notifications, backend rate-limit mapping, workspace behavior, error formatting, and Python SDK response coercion for the new plan value.

GitOrigin-RevId: 70bc17a7c4ba4028cb10e4333cc1f2ac64da361f

sdk/python/scripts/update_sdk_artifacts.py

@@ -608,6 +608,7 @@ def generate_v2_all(schema_dir: Path) -> None:
     _require_nullable_chatgpt_account_email(out_path)
     _preserve_reasoning_effort_enum(out_path)
     _preserve_thread_source_enum(out_path)
+    _preserve_plan_type_enum(out_path)
     _normalize_generated_timestamps(out_path)
 
 
@@ -695,6 +696,36 @@ def _preserve_thread_source_enum(out_path: Path) -> None:
     out_path.write_text(source[:class_start] + open_enum + source[class_end:])
 
 
+def _preserve_plan_type_enum(out_path: Path) -> None:
+    """Keep the public plan constants while accepting values from newer runtimes."""
+    source = out_path.read_text()
+    class_start = source.find("class PlanType(Enum):")
+    if class_start == -1:
+        raise RuntimeError("Generated SDK is missing PlanType")
+    class_end = source.find("\n\nclass ", class_start)
+    if class_end == -1:
+        class_end = len(source)
+
+    class_source = source[class_start:class_end]
+    class_source = class_source.replace(
+        "class PlanType(Enum):",
+        "class PlanType(str, Enum):",
+        1,
+    ).rstrip()
+    class_source += """
+
+    @classmethod
+    def _missing_(cls, value: object) -> PlanType | None:
+        if not isinstance(value, str) or not value:
+            return None
+        member = str.__new__(cls, value)
+        member._name_ = value
+        member._value_ = value
+        return member
+"""
+    out_path.write_text(source[:class_start] + class_source + source[class_end:])
+
+
 def _notification_specs(schema_dir: Path) -> list[tuple[str, str]]:
     """Map each server notification method to its generated payload model class."""
     server_notifications = json.loads((schema_dir / "ServerNotification.json").read_text())