Remove unused default_group_name from ModelProto and implementations (#144)

The `default_group_name` method was defined in the `ModelProto` protocol
but no longer needed.

## Changes

- **`qmp/utility/model_dict.py`**: Removed `default_group_name`
classmethod from `ModelProto` protocol
- **`qmp/models/{fcidump,hubbard,free_fermion,ising,openfermion}.py`**:
Removed `default_group_name` implementations from all model classes

Total: 53 lines removed across 6 files.

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> 
> *This section details on the original issue you should resolve*
> 
> <issue_title>/qmp/utility/model_dict.py 中的 default_group_name 和
qmp/models 下各个实现不需要了， 把这个default group name删了</issue_title>
> <issue_description></issue_description>
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- Fixes #143

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Author: hzhangxyz

qmp/models/fcidump.py

@@ -132,10 +132,6 @@ class Model(ModelProto[ModelConfig]):
 
     config_t = ModelConfig
 
-    @classmethod
-    def default_group_name(cls, config: ModelConfig) -> str:
-        return config.model_name
-
     def __init__(self, args: ModelConfig) -> None:
         # pylint: disable=too-many-locals
         logging.info("Input arguments successfully parsed")

qmp/models/free_fermion.py

@@ -42,10 +42,6 @@ class Model(ModelProto[ModelConfig]):
 
     config_t = ModelConfig
 
-    @classmethod
-    def default_group_name(cls, config: ModelConfig) -> str:
-        return f"FreeFermion_{config.m}x{config.n}_e{config.electron_number}"
-
     @classmethod
     def _prepare_hamiltonian(cls, args: ModelConfig) -> dict[tuple[tuple[int, int], ...], complex]:
         def _index(i: int, j: int) -> int:

qmp/models/hubbard.py

@@ -55,10 +55,6 @@ class Model(ModelProto[ModelConfig]):
 
     config_t = ModelConfig
 
-    @classmethod
-    def default_group_name(cls, config: ModelConfig) -> str:
-        return f"Hubbard_{config.m}x{config.n}_t{config.t}_u{config.u}_e{config.electron_number}"
-
     @classmethod
     def _prepare_hamiltonian(cls, args: ModelConfig) -> dict[tuple[tuple[int, int], ...], complex]:
         def _index(i: int, j: int, o: int) -> int:

qmp/models/ising.py

@@ -70,27 +70,6 @@ class Model(ModelProto[ModelConfig]):
 
     config_t = ModelConfig
 
-    @classmethod
-    def default_group_name(cls, config: ModelConfig) -> str:
-        # pylint: disable=too-many-locals
-        x = f"_x{config.x}" if config.x != 0 else ""
-        y = f"_y{config.y}" if config.y != 0 else ""
-        z = f"_z{config.z}" if config.z != 0 else ""
-        xh = f"_xh{config.xh}" if config.xh != 0 else ""
-        yh = f"_yh{config.yh}" if config.yh != 0 else ""
-        zh = f"_zh{config.zh}" if config.zh != 0 else ""
-        xv = f"_xv{config.xv}" if config.xv != 0 else ""
-        yv = f"_yv{config.yv}" if config.yv != 0 else ""
-        zv = f"_zv{config.zv}" if config.zv != 0 else ""
-        xd = f"_xd{config.xd}" if config.xd != 0 else ""
-        yd = f"_yd{config.yd}" if config.yd != 0 else ""
-        zd = f"_zd{config.zd}" if config.zd != 0 else ""
-        xa = f"_xa{config.xa}" if config.xa != 0 else ""
-        ya = f"_ya{config.ya}" if config.ya != 0 else ""
-        za = f"_za{config.za}" if config.za != 0 else ""
-        desc = x + y + z + xh + yh + zh + xv + yv + zv + xd + yd + zd + xa + ya + za
-        return f"Ising_{config.m}_{config.n}" + desc
-
     @classmethod
     def _prepare_hamiltonian(cls, args: ModelConfig) -> dict[tuple[tuple[int, int], ...], complex]:
         # pylint: disable=too-many-branches

qmp/models/openfermion.py

@@ -40,10 +40,6 @@ class Model(ModelProto[ModelConfig]):
 
     config_t = ModelConfig
 
-    @classmethod
-    def default_group_name(cls, config: ModelConfig) -> str:
-        return config.model_name
-
     def __init__(self, args: ModelConfig) -> None:
         logging.info("Input arguments successfully parsed")
         logging.info("Model path: %s", args.model_path)

qmp/utility/model_dict.py

@@ -107,22 +107,6 @@ class ModelProto(typing.Protocol[ModelConfig]):
 
     config_t: type[ModelConfig]
 
-    @classmethod
-    def default_group_name(cls, config: ModelConfig) -> str:
-        """
-        Get the default group name for logging purposes.
-
-        Parameters
-        ----------
-        config : ModelConfig
-            The config of model.
-
-        Returns
-        -------
-        str
-            The group name for logging purposes.
-        """
-
     def __init__(self, config: ModelConfig) -> None:
         """
         Create a model from the given config.