chore: Remove entproto command and related entity code

Deleted the entproto command, its documentation, and all related internal entity code including graph, proto generation, and mapper logic. This simplifies the codebase by removing Ent-to-Protobuf and Ent-mapper generation features.

Author: tbxark

README.md

@@ -58,29 +58,6 @@ sphere-cli create list
 
 ---
 
-### `entproto`
-
-Converts Ent schemas into Protobuf (`.proto`) definitions. This command reads your Ent schema files and generates corresponding `.proto` files.
-
-**Usage:**
-```shell
-sphere-cli entproto [flags]
-```
-
-**Flags:**
-- `--path string`: Path to the Ent schema directory (default: `./schema`).
-- `--proto string`: Output directory for the generated `.proto` files (default: `./proto`).
-- `--all_fields_required`: Treat all fields as required, ignoring `Optional()` (default: `true`).
-- `--auto_annotation`: Automatically add `@entproto` annotations to the schema (default: `true`).
-- `--enum_raw_type`: Use `string` as the type for enums in Protobuf (default: `true`).
-- `--skip_unsupported`: Skip fields with types that are not supported (default: `true`).
-- `--time_proto_type string`: Protobuf type to use for `time.Time` fields. Options: `int64`, `string`, `google.protobuf.Timestamp` (default: `int64`).
-- `--uuid_proto_type string`: Protobuf type to use for `uuid.UUID` fields. Options: `string`, `bytes` (default: `string`).
-- `--unsupported_proto_type string`: Protobuf type to use for unsupported fields. Options: `google.protobuf.Any`, `google.protobuf.Struct`, `bytes` (default: `google.protobuf.Any`).
-- `--import_proto string`: Define external Protobuf imports. Format: `path1,package1,type1;path2,package2,type2` (default: `google/protobuf/any.proto,google.protobuf,Any;`).
-
----
-
 ### `service`
 
 Generates service code, including both Protobuf definitions and Go service implementations.