**Refactor:** Restructure server package to streamline imports and improve file organization

- Moved `providers`, `services`, `models`, `lib`, and related files to `src` directory within `server` package.
- Adjusted imports across the codebase to reflect the new paths.
- Renamed several `.ts` files for consistency.
- Introduced an `index.ts` in the `ai/providers` package to export all providers.

This improves maintainability and aligns with the project's updated directory structure.

packages/ai/providers/google.ts

@@ -0,0 +1,72 @@
+import { type StreamParams } from '@open-gsio/server/src/services/ChatService';
+import { OpenAI } from 'openai';
+
+import { ProviderRepository } from './_ProviderRepository.ts';
+import { BaseChatProvider, type CommonProviderParams } from './chat-stream-provider.ts';
+
+export class GoogleChatProvider extends BaseChatProvider {
+  getOpenAIClient(param: CommonProviderParams): OpenAI {
+    return new OpenAI({
+      baseURL: ProviderRepository.OPENAI_COMPAT_ENDPOINTS.google,
+      apiKey: param.env.GEMINI_API_KEY,
+    });
+  }
+
+  getStreamParams(param: CommonProviderParams, safeMessages: any[]): any {
+    return {
+      model: param.model,
+      messages: safeMessages,
+      stream: true,
+    };
+  }
+
+  async processChunk(chunk: any, dataCallback: (data: any) => void): Promise<boolean> {
+    if (chunk.choices?.[0]?.finish_reason === 'stop') {
+      dataCallback({
+        type: 'chat',
+        data: {
+          choices: [
+            {
+              delta: { content: chunk.choices[0].delta.content || '' },
+              finish_reason: 'stop',
+              index: chunk.choices[0].index,
+            },
+          ],
+        },
+      });
+      return true;
+    } else {
+      dataCallback({
+        type: 'chat',
+        data: {
+          choices: [
+            {
+              delta: { content: chunk.choices?.[0]?.delta?.content || '' },
+              finish_reason: null,
+              index: chunk.choices?.[0]?.index || 0,
+            },
+          ],
+        },
+      });
+      return false;
+    }
+  }
+}
+
+export class GoogleChatSdk {
+  private static provider = new GoogleChatProvider();
+
+  static async handleGoogleStream(param: StreamParams, dataCallback: (data: any) => void) {
+    return this.provider.handleStream(
+      {
+        systemPrompt: param.systemPrompt,
+        preprocessedContext: param.preprocessedContext,
+        maxTokens: param.maxTokens,
+        messages: param.messages,
+        model: param.model,
+        env: param.env,
+      },
+      dataCallback,
+    );
+  }
+}