* support assign op

* support assign infer_var_type

* change code according to review

* change code according to review

* only save 'get_infer_var_type_func'

* rest file mode

* migrate assign xpu kernel, test=kunlun

* remove assign_value xpu, test=kunlun

* refactor the optional tensor

* remove optiona<MetaTensor> in InferMeta

* fix bug

* fix optional<vector<Tensor>>

* fix bug

* fix rmsprop

* fix amp of eager_gen

* polish code

* fix deleted code

* fix merge conflict

* polish code

* remove is_nullopt_

* fix merge conflict

* fix merge conflict

* move assign kernel init commit

* change vec<tensor> to vec<tensor*>

* support tensor array

* support api declare

* fix test_list failed

* fix npu and xpu failed

* fix infrt failed

* remove assign array size in operator

* move assign sr header into sr dir

* add infermeta for assign

* test op success

* fix test_list failed

* fix kunlun failed

* add set host allocator in tests

* support tensor array in arg ctx

* open set layout in share_meta

* fix meta tensor layout error

* fix test failed