feat(lora): support relative paths in <lora:folder/name:strength> syntax (#917)

Autocomplete, copy/send-to-workflow, and recipe syntax now emit
<lora:folder/name:strength> instead of <lora:name:strength>, using
relative paths to disambiguate identically-named loras in different
subfolders without requiring file renames.

Backend: 3-tier hybrid resolution (path → bare → basename fallback)
across get_lora_info, get_lora_info_absolute, get_model_preview_url,
get_model_civitai_url, get_model_info_by_name, get_lora_metadata_by_filename,
and get_hash_by_filename. Also fix get_random_loras and get_cycler_list
to return path-prefixed names for randomizer/cycler consistency.

Frontend: autocomplete, copyLoraSyntax, handleSendToWorkflow emit
folder-prefixed syntax. extract_lora_name preserves relative paths.

Saved image metadata (<lora:...> in EXIF) intentionally keeps basename-only
for compatibility with A1111/Forge ecosystem.

py/services/model_hash_index.py

@@ -209,7 +209,9 @@ class ModelHashIndex:
         return self._filename_to_hash.get(filename)
     
     def get_hash_by_filename(self, filename: str) -> Optional[str]:
-        """Get hash for a filename without extension"""
+        """Get hash for a filename (bare basename or path-prefixed name)"""
+        if "/" in filename or "\\" in filename:
+            filename = os.path.splitext(os.path.basename(filename.replace("\\", "/")))[0]
         return self._filename_to_hash.get(filename)
     
     def clear(self) -> None: