feat(server): wire HTTP transport into CLI, add docker-compose.server.yml, and update docs

docs/DECISIONS.md

@@ -363,3 +363,38 @@ Users and client LLM applications (such as Claude Desktop, Cursor, or containeri
 - Provides seamless Docker execution for desktop and server MCP clients via `docker run -i --rm ghcr.io/<owner>/openproject-mcp:latest`.
 - Prevents container build regressions through automated PR verification.
 - Guarantees multi-architecture compatibility across Apple Silicon and x86_64 host machines.
+
+---
+
+## ADR-016: Hosted Remote MCP Server Architecture (HTTP/SSE Transport) & Multi-Tenant Credential Scoping
+
+### Status
+Accepted
+
+### Context
+`openproject-mcp` initially executed exclusively as a local child process over standard input/output (`stdio`). While ideal for individual developers running local tools like Claude Desktop or Cursor on their personal machines, team environments, shared hosting, and web agents require a remotely hosted MCP server instance accessible over standard network protocols.
+
+Key requirements for hosted operation:
+1. **Multi-Tenant Credential Scoping**: A single server process connects to a shared OpenProject base URL (`OPENPROJECT_BASE_URL`), but every connecting user/agent must use their own personal OpenProject API token. User credentials must never bleed across sessions or be retained in global mutable memory.
+2. **Dual-Transport Entrypoint**: The server CLI must support both local stdio execution and hosted HTTP/SSE execution via configuration (`PORT` / `--port`).
+3. **Flexible Authentication**: Clients must be able to authenticate via standard headers (`Authorization: Bearer <key>`, `X-OpenProject-Api-Key: <key>`) or query parameters (`?apiKey=<key>`) for SSE-compatible desktop and web clients.
+4. **Health & Lifecycle Management**: Provide standardized `/health` endpoints and clean session eviction on client disconnect to prevent memory leaks.
+
+### Decision
+1. **HTTP/SSE Transport Engine**: Implement `src/http-server.ts` utilizing native `Bun.serve` and Web Streams for Server-Sent Events (`text/event-stream`).
+2. **Credential Extraction Precedence**:
+   - Priority 1: `Authorization: Bearer <token>`
+   - Priority 2: `X-OpenProject-Api-Key: <token>`
+   - Priority 3: `?apiKey=<token>` URL query parameter
+   - Reject unauthenticated `/sse` requests immediately with HTTP 401 Unauthorized.
+3. **Per-Connection Isolation**: For each `/sse` connection, allocate a unique `sessionId` and initialize an isolated `OpenProjectClient` and `McpServer` instance. Route tool calls and JSON-RPC dispatch via `runWithContext` using `AsyncLocalStorage`.
+4. **Session Eviction**: Register connection abort and stream cancellation handlers (`req.signal.addEventListener("abort")` and `stream.cancel()`) that evict disconnected sessions from active memory.
+5. **Container Deployment**: Provide `docker-compose.server.yml` with built-in `/health` probe checking `GET /health` every 30s.
+
+### Consequences
+- **Positive**:
+  - Organizations can deploy a single shared `openproject-mcp` service without sharing API tokens.
+  - Full compatibility with remote MCP client connections in Cursor, Claude Desktop, and autonomous agents.
+  - Backward compatibility: when `PORT` is not set, stdio transport remains the default with zero overhead.
+- **Negative**:
+  - Requires network infrastructure (e.g. reverse proxy with TLS termination) in production to protect credentials in transit.

docs/TODO.md

@@ -96,10 +96,23 @@
   - [x] Recorded [ADR-015](DECISIONS.md#adr-015-docker-container-packaging-and-github-actions-cicd-pipeline).
   - [x] Updated [README.md](../README.md) with Docker Quickstart, read-only mode instructions, and client integration settings (Claude Desktop & Cursor).
 
+- [x] **Task 7: Hosted Remote MCP Server (HTTP/SSE Transport) & Multi-Tenant Credential Scoping**
+  - [x] Extend configuration loader with `port` and `host` options (`src/config/index.ts`, `tests/config.test.ts`).
+  - [x] Implement hosted HTTP/SSE MCP server with `Bun.serve` and Web Streams SSE (`src/http-server.ts`, `tests/http-server.test.ts`).
+  - [x] Implement credential extraction hierarchy (`Authorization: Bearer`, `X-OpenProject-Api-Key`, `?apiKey=`) with 401 unauthorized rejection.
+  - [x] Implement per-session client isolation and `runWithContext` dynamic scoping.
+  - [x] Wire dual-transport execution in CLI entrypoint (`src/index.ts`).
+  - [x] Create production `docker-compose.server.yml` with `/health` check probe.
+  - [x] Record [ADR-016](DECISIONS.md#adr-016-hosted-remote-mcp-server-architecture-httpsse-transport--multi-tenant-credential-scoping).
+  - [x] Update documentation with hosted deployment guide and remote client setups for Cursor and Claude Desktop in [README.md](../README.md).
+
 ---
 
 ## 3. Backlog & Future Phases
 
+- [x] **Phase 4: Remote Transport (Completed)**
+  - [x] Add SSE (Server-Sent Events) transport option for remote deployments.
+  - [x] Multi-tenant credential scoping with per-session isolation.
 - [ ] **Phase 2: Mutating Operations**
   - [ ] Create work package tool (`openproject_create_work_package`).
   - [ ] Update work package tool (`openproject_update_work_package`).
@@ -108,5 +121,3 @@
 - [ ] **Phase 3: Attachments & Documents**
   - [ ] Inspect and download attachment resources.
   - [ ] Wiki pages and project documents browsing.
-- [ ] **Phase 4: Remote Transport**
-  - [ ] Add SSE (Server-Sent Events) transport option for remote deployments.