Function miracle_queue_custom_animation 

pub unsafe extern "C" fn miracle_queue_custom_animation(
    plugin_handle: i32,
    out_animation_id_ptr: i32,
    duration_seconds_ptr: i32,
) -> i32

Queue a custom per-frame animation.

The compositor will call the plugin’s custom_animate WASM export each frame until the plugin returns 1 (complete). The plugin is responsible for all visual side effects via the existing host functions.

plugin_handle should be the value from miracle_get_plugin_handle(). out_animation_id_ptr is a WASM memory offset where the host will write the generated unique animation ID as a uint32_t.

Returns 0 on success, -1 on error.