docs: add upstage/solar-pro-3 (#389)

Author: StanAIML

docs/SUMMARY.md

@@ -278,6 +278,8 @@
     * [Unslopnemo 12B](api-references/text-models-llm/TheDrummer/unslopnemo-12b.md)
   * [undi95](api-references/text-models-llm/undi95/README.md)
     * [ReMM SLERP 13B](api-references/text-models-llm/undi95/remm-slerp-l2-13b.md)
+  * [Upstage](api-references/text-models-llm/Upstage/README.md)
+    * [Solar Pro 3](api-references/text-models-llm/Upstage/solar-pro-3.md)
   * [xAI](api-references/text-models-llm/xAI/README.md)
     * [Grok 3 Beta](api-references/text-models-llm/xai/grok-3-beta.md)
     * [Grok 3 Mini Beta](api-references/text-models-llm/xai/grok-3-mini-beta.md)

docs/api-references/model-database.md

@@ -0,0 +1,2 @@
+# Upstage
+