refactor(mnn): remove unused model loading methods from mnn.rs files

Cargo.toml

@@ -5,15 +5,12 @@ members = ["ndarray-image", "ndarray-resize", ".", "bounding-box"]
 version = "0.1.0"
 edition = "2024"
 
-[patch."https://github.com/uttarayan21/mnn-rs"]
-mnn = { path = "/Users/fs0c131y/Projects/aftershoot/mnn-rs" }
-
 [workspace.dependencies]
 ndarray-image = { path = "ndarray-image" }
 ndarray-resize = { path = "ndarray-resize" }
 mnn = { git = "https://github.com/uttarayan21/mnn-rs", version = "0.2.0", features = [
-    "metal",
-    "coreml",
+    # "metal",
+    # "coreml",
     "tracing",
 ], branch = "restructure-tensor-type" }
 mnn-bridge = { git = "https://github.com/uttarayan21/mnn-rs", version = "0.1.0", features = [
@@ -53,7 +50,11 @@ bounding-box = { version = "0.1.0", path = "bounding-box" }
 color = "0.3.1"
 itertools = "0.14.0"
 ordered-float = "5.0.0"
-ort = { version = "2.0.0-rc.10", default-features = false, features = [ "std", "tracing", "ndarray"]}
+ort = { version = "2.0.0-rc.10", default-features = false, features = [
+    "std",
+    "tracing",
+    "ndarray",
+] }
 
 [profile.release]
 debug = true
@@ -65,5 +66,7 @@ ort-tensorrt = ["ort/tensorrt"]
 ort-tvm = ["ort/tvm"]
 ort-openvino = ["ort/openvino"]
 ort-directml = ["ort/directml"]
+mnn-metal = ["mnn/metal"]
+mnn-coreml = ["mnn/coreml"]
 
-default = ["ort-coreml"]
+default = []