feat(coreml): publish fp16 only, drop the fp32 build

fp16 was validated against fp32 across 13 real photos and 40 detections: visible landmarks agree to 1.04 px, boxes to 0.653 px and scores to 0.072, with no detection crossing the confidence threshold. It is also faster (144.0 ms against 165.1), lighter (263 MB peak against 389 MB) and half the download, so there is no longer a reason to ship both.

v0.9.0 retains its own copy of the fp32 file; released versions are unaffected.

From export-scripts MR !18.

preview/coreml/config.json

@@ -51,50 +51,6 @@
           ]
         }
       }
-    },
-    {
-      "file": "rfdetr_keypoint_preview_coreml_fp32.pte",
-      "precision": "fp32",
-      "quantized": false,
-      "default": false,
-      "methods": {
-        "forward": {
-          "inputs": [
-            {
-              "shape": [
-                1,
-                3,
-                576,
-                576
-              ],
-              "dtype": "float32"
-            }
-          ],
-          "outputs": [
-            {
-              "shape": [
-                100,
-                4
-              ],
-              "dtype": "float32"
-            },
-            {
-              "shape": [
-                100
-              ],
-              "dtype": "float32"
-            },
-            {
-              "shape": [
-                100,
-                17,
-                3
-              ],
-              "dtype": "float32"
-            }
-          ]
-        }
-      }
     }
   ]
 }

preview/coreml/rfdetr_keypoint_preview_coreml_fp32.pte

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:0455df2be527a464bba13876ab5cd1a2becbfb0e7a2d0dcc826c5e095bd6bffe
-size 147743446