add initial support for Fireworks provider (#16)

* add initial support for Fireworks provider

* Refactor Fireworks provider with improved error handling and stream processing

* fix for types

* remove unused secret keys from global state

* add completePrompt method for Fireworks

* add deepseek-v3 from Fireworks and minor refactor for model selection

* add some tests

* rollback type check

* rollback validation on submit

* ups

* rollback to original WelcomeView

* fix comment about JSON errors

* reset ModelPicker.tsx and WelcomeView.tsx to match main

* fix merging

* remove retry helper

* fallback to main

* move Fireworks provider up

I also moved the Fireworks code to be close the Kilocode provider

* add 403 error code

* add troubleshooting link

* remove destructuring

Author: ofou

src/api/index.ts

@@ -21,6 +21,7 @@ import { UnboundHandler } from "./providers/unbound"
 import { RequestyHandler } from "./providers/requesty"
 import { HumanRelayHandler } from "./providers/human-relay"
 import { KiloCodeHandler } from "./providers/kilocode"
+import { FireworksHandler } from "./providers/fireworks"
 
 export interface SingleCompletionHandler {
 	completePrompt(prompt: string): Promise<string>
@@ -78,6 +79,8 @@ export function buildApiHandler(configuration: ApiConfiguration): ApiHandler {
 			return new RequestyHandler(options)
 		case "human-relay":
 			return new HumanRelayHandler(options)
+		case "fireworks":
+			return new FireworksHandler(options)
 		default:
 			return new AnthropicHandler(options)
 	}