docs: model benchmarks (#17036)

* model benchmarks

* minor fixes

* formatting

* docs build

* maybe fix reference

* clarify optimal

* use emojis

* wording

* wording

* clarify optimal wording

* bolding

* more detailed instructions

* clarify edge case fix

* early exit in dim loop

machine-learning/export/immich_model_exporter/get_dims.py

@@ -0,0 +1,22 @@
+import json
+from pathlib import Path
+
+models_dir = Path("models")
+model_to_embed_dim = {}
+for model_dir in models_dir.iterdir():
+    if not model_dir.is_dir():
+        continue
+
+    config_path = model_dir / "config.json"
+    if not config_path.exists():
+        print(f"Skipping {model_dir.name} as it does not have a config.json")
+        continue
+    with open(config_path) as f:
+        config = json.load(f)
+        embed_dim = config.get("embed_dim")
+        if embed_dim is None:
+            print(f"Skipping {model_dir.name} as it does not have an embed_dim")
+            continue
+        print(f"{model_dir.name}: {embed_dim}")
+        model_to_embed_dim[model_dir.name] = {"dimSize": embed_dim}
+print(json.dumps(model_to_embed_dim))