fix(diffusers): add support for diffusers SDXL text encoder prefixes

Problem: SDXL models in diffusers directory format fail to load with "unknown tensor" errors
Solution: Added te. and te.1. prefixes to cond_stage_model conversion list
Testing: SDXL diffusers models now load and generate successfully

Root cause: When loading diffusers SDXL models, text_encoder uses "te." prefix
and text_encoder_2 uses "te.1." prefix. These weren't in the name conversion
prefix list, so tensors weren't being converted to checkpoint format names.

This fix enables diffusers-format SDXL models to work alongside single-file
checkpoint models without requiring format conversion.

Fixes: Models like duchaiten-pony-real-v20-sdxl in diffusers directory layout

Author: fewtarius

src/name_conversion.cpp

@@ -920,6 +920,8 @@ std::vector<std::string> cond_stage_model_prefix_vec = {
     "cond_stage_model.",
     "conditioner.embedders.",
     "text_encoders.",
+    "te.1.",  // diffusers SDXL text_encoder_2 (clip_g)
+    "te.",    // diffusers text_encoder (clip_l)
 };
 
 std::vector<std::string> diffuison_model_prefix_vec = {