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# Issue #3: Configure Caddy for gRPC-Web support

**Status:** COMPLETED
**Issue:** https://git.shahondin1624.de/llm-multiverse/llm-multiverse-ui/issues/3
**Branch:** `feature/issue-3-caddy-grpc-web`

## Summary

Create a Caddyfile that handles gRPC-Web translation, CORS headers, and proxies both gRPC-Web traffic to the Orchestrator and regular traffic to the SvelteKit dev server.

## Acceptance Criteria

- [x] Caddyfile with gRPC-Web reverse proxy configuration
- [x] CORS headers configured for local dev and production origins
- [x] Content-Type mapping for gRPC-Web ↔ gRPC translation
- [x] grpc_web directive enabled (via content-type matching + h2c transport)
- [x] Documented how to run Caddy alongside the orchestrator
- [x] Browser can successfully call the Orchestrator through Caddy

## Implementation

Single Caddyfile in the project root that:
1. Routes `application/grpc-web*` requests to the Orchestrator via h2c
2. Handles CORS preflight (OPTIONS) with configurable origin
3. Adds CORS response headers for gRPC-Web responses
4. Routes all other traffic to the SvelteKit dev server
5. Configurable via environment variables: ORCHESTRATOR_HOST, UI_HOST, DOMAIN, TLS_MODE, CORS_ORIGIN

## Deviations

- Caddy v2 doesn't have a built-in `grpc_web` directive. Instead, we match on Content-Type headers and use h2c transport, which is the standard Caddy approach for gRPC-Web proxying. The Connect protocol used by connect-es handles the gRPC-Web encoding/decoding on the client side.