The `_ready_event` is now set in `GatewayClient` immediately after
receiving the `READY` payload, before dispatching `on_ready` to user code.
This ensures `Client.wait_until_ready()` and `Client.is_ready()`
accurately reflect the client's state before dependent user logic executes.
This change allows simplifying `Client.sync_commands` by removing
redundant `wait_until_ready()` calls and `application_id` checks,
as the application ID is guaranteed to be available upon READY.
Additionally, `User` model initialization is improved to correctly handle
nested user data found in certain API payloads (e.g., within `member`
objects in events like `PresenceUpdate`).
Add `SOUNDBOARD` and `VIDEO_QUALITY_720_60FPS` to `GuildFeature` enum.
Lowers minimum Python requirement from 3.11 to 3.10 to increase compatibility while updating CI to use Python 3.13 for testing.
Extracts hybrid command functionality into a separate module to improve code organization and reduce complexity in the main commands module.
Updates test timeouts and dependency versions to ensure reliable test execution and modern package compatibility.
