⚡ Introduce a new high-performing standalone chat API (#1200)

Closes #1154

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

- **New Features**
	- Added authentication functionality for user sessions in chat API.
- Introduced chat-related API endpoints for starting, previewing, and
continuing chat sessions, and streaming messages.
- Implemented WhatsApp API webhook handling for receiving and processing
messages.
- Added environment variable `NEXT_PUBLIC_CHAT_API_URL` for chat API URL
configuration.

- **Bug Fixes**
	- Adjusted file upload logic to correctly determine the API host.
	- Fixed message streaming URL in chat integration with OpenAI.

- **Documentation**
- Updated guides for creating blocks, local installation, self-hosting,
and deployment to use `bun` instead of `pnpm`.

- **Refactor**
	- Refactored chat API functionalities to use modular architecture.
- Simplified client log saving and session update functionalities by
using external functions.
	- Transitioned package management and workflow commands to use `bun`.

- **Chores**
- Switched to `bun` for package management in Dockerfiles and GitHub
workflows.
	- Added new Dockerfile for chat API service setup with Bun framework.
	- Updated `.prettierignore` and documentation with new commands.

- **Style**
	- No visible changes to end-users.

- **Tests**
	- No visible changes to end-users.

- **Revert**
	- No reverts in this release.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

chatApi.Dockerfile

@@ -0,0 +1,21 @@
+FROM oven/bun
+
+WORKDIR /app
+
+COPY . .
+
+RUN apt-get -qy update && apt-get -qy --no-install-recommends install openssl ca-certificates git -y && update-ca-certificates
+
+RUN bun install
+
+# Need Node for Prisma
+COPY --from=node:18 /usr/local/bin/node /usr/local/bin/node
+RUN bun /app/packages/prisma/scripts/db-exec.ts "bunx prisma generate"
+
+RUN rm -rf /usr/local/bin/node
+RUN rm -rf /app/apps/builder
+RUN rm -rf /app/apps/viewer
+
+ENV PORT=3000
+EXPOSE 3000
+CMD ["bun", "run", "apps/chat-api/src/index.ts"]