feat: add chat and file management APIs, implement chat loading and saving functionality

- Introduced new API endpoints for chat management including posting and retrieving chat messages.
- Implemented file upload and deletion functionalities for chat and other files.
- Added utility functions for streaming text and loading chat data.
- Created TypeScript types for models and agents used in the application.
- Configured TypeScript settings for server and project.
- Added favicon and workspace configuration for pnpm.

server/utils/stream.ts

@@ -0,0 +1,13 @@
+export async function streamToText(stream: ReadableStream<Uint8Array>) {
+  const reader = stream.getReader()
+  const decoder = new TextDecoder()
+  let result = ''
+
+  while (true) {
+    const { done, value } = await reader.read()
+    if (done) break
+    result += decoder.decode(value, { stream: true })
+  }
+
+  return result
+}