feat(19-02): extract provider types to providers.ts

Create providers.ts with ProviderType, SelectedModel, ProviderConfig,
ProviderSettings, LLMProvider, and LLMModelType. Update index.ts to
re-export from providers.ts and import types for internal use.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/types/index.ts

@@ -3,6 +3,18 @@ import { Edge } from "@xyflow/react";
 // Re-export all node and annotation types from domain files
 export * from "./annotation";
 export * from "./nodes";
+export * from "./providers";
+
+// Recently used models tracking
+export interface RecentModel {
+  provider: ProviderType;
+  modelId: string;
+  displayName: string;
+  timestamp: number;
+}
+
+// Import provider types for use in this file
+import type { ProviderType, LLMProvider, LLMModelType } from "./providers";
 
 // Aspect Ratios (supported by both Nano Banana and Nano Banana Pro)
 export type AspectRatio = "1:1" | "2:3" | "3:2" | "3:4" | "4:3" | "4:5" | "5:4" | "9:16" | "16:9" | "21:9";
@@ -13,17 +25,6 @@ export type Resolution = "1K" | "2K" | "4K";
 // Image Generation Model Options
 export type ModelType = "nano-banana" | "nano-banana-pro";
 
-// LLM Provider Options
-export type LLMProvider = "google" | "openai";
-
-// LLM Model Options
-export type LLMModelType =
-  | "gemini-2.5-flash"
-  | "gemini-3-flash-preview"
-  | "gemini-3-pro-preview"
-  | "gpt-4.1-mini"
-  | "gpt-4.1-nano";
-
 // Workflow Edge Data
 export interface WorkflowEdgeData extends Record<string, unknown> {
   hasPause?: boolean;
@@ -102,24 +103,3 @@ export interface NodeGroup {
   locked?: boolean;
 }
 
-// Provider Types for multi-provider support
-export type ProviderType = "gemini" | "openai" | "replicate" | "fal";
-
-// Selected model for image/video generation nodes
-export interface SelectedModel {
-  provider: ProviderType;
-  modelId: string;
-  displayName: string;
-}
-
-export interface ProviderConfig {
-  id: ProviderType;
-  name: string;
-  enabled: boolean;
-  apiKey: string | null;
-  apiKeyEnvVar?: string;  // For providers using environment variables (e.g., Gemini)
-}
-
-export interface ProviderSettings {
-  providers: Record<ProviderType, ProviderConfig>;
-}

src/types/providers.ts

@@ -0,0 +1,39 @@
+/**
+ * Provider Types
+ *
+ * Types for multi-provider support including image generation
+ * providers and LLM providers.
+ */
+
+// Provider Types for multi-provider support (image/video generation)
+export type ProviderType = "gemini" | "openai" | "replicate" | "fal";
+
+// Selected model for image/video generation nodes
+export interface SelectedModel {
+  provider: ProviderType;
+  modelId: string;
+  displayName: string;
+}
+
+export interface ProviderConfig {
+  id: ProviderType;
+  name: string;
+  enabled: boolean;
+  apiKey: string | null;
+  apiKeyEnvVar?: string; // For providers using environment variables (e.g., Gemini)
+}
+
+export interface ProviderSettings {
+  providers: Record<ProviderType, ProviderConfig>;
+}
+
+// LLM Provider Options
+export type LLMProvider = "google" | "openai";
+
+// LLM Model Options
+export type LLMModelType =
+  | "gemini-2.5-flash"
+  | "gemini-3-flash-preview"
+  | "gemini-3-pro-preview"
+  | "gpt-4.1-mini"
+  | "gpt-4.1-nano";