feat: legacy features to ruby llm (#12994)

lib/llm_constants.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+module LlmConstants
+  DEFAULT_MODEL = 'gpt-4.1-mini'
+  DEFAULT_EMBEDDING_MODEL = 'text-embedding-3-small'
+  PDF_PROCESSING_MODEL = 'gpt-4.1-mini'
+
+  OPENAI_API_ENDPOINT = 'https://api.openai.com'
+
+  PROVIDER_PREFIXES = {
+    'openai' => %w[gpt- o1 o3 o4 text-embedding- whisper- tts-],
+    'anthropic' => %w[claude-],
+    'google' => %w[gemini-],
+    'mistral' => %w[mistral- codestral-],
+    'deepseek' => %w[deepseek-]
+  }.freeze
+end