### Godot version

4.2 RC2

### System information

Any

### Issue description

AnimationMixer separates the accuracy of how discrete keys are retrieved when seeking between internal seeking and external seeking. FYI: https://github.com/godotengine/godot/pull/80708.

Since AnimationPlayer currently treats everything as an internal seek, so it needs to propagate the external seek information.

### Steps to reproduce

Seek AnimationTrackEditor

### Minimal reproduction project

[gd_anim_unittest_1.zip](https://github.com/godotengine/godot/files/13492063/gd_anim_unittest_1.zip)

String name = p_name;
	if (name == "playback/play") { 
		r_ret = get_current_animation();
	} else if (name.begins_with("next/")) {
		String which = name.get_slicec('/', 1);
		r_ret = animation_get_next(which);
	} else if (name == "blend_times") {
		Vector<BlendKey> keys;
		for (const KeyValue<BlendKey, double> &E : blend_times) {
			keys.ordered_insert(E.key);
		}
		Array array;
		for (int i = 0; i < keys.size(); i++) {
			array.push_back(keys[i].from);
			array.push_back(keys[i].to);
			array.push_back(blend_times.get(keys[i]));
		}
		r_ret = array;
#ifndef DISABLE_DEPRECATED
	} else if (name == "method_call_mode") {