fix(deploy): use repo-root build context in coolify compose

Coolify invokes `docker compose` with --project-directory set to the
repository root, not this file's directory. Previous `context: ..` was
resolving to /artifacts (one level above the repo) and failing with
`resolve : lstat /artifacts/docker: no such file or directory`.

Switch all three services (web, collab, mcp) to `context: .` so the
build context is the repo root and `dockerfile: docker/Dockerfile.X`
resolves correctly.

Made-with: Cursor

docker/docker-compose.coolify.yml

@@ -7,16 +7,20 @@
 #   - Set domains in Coolify on the `web` and `collab` services using http://
 #     (CT 100 Traefik handles TLS termination per AGENT-DEPLOY.md)
 #
+# Path conventions:
+#   Coolify invokes `docker compose` with --project-directory set to the
+#   repository root, NOT this file's directory. So all build contexts and
+#   dockerfile paths below are written relative to the repo root.
+#
 # Differences vs. docker/docker-compose.yml:
 #   - No bundled postgres / redis (uses shared CT 102 services)
 #   - No host port mappings (Coolify's Traefik routes by container labels)
 #   - Uses Coolify SERVICE_FQDN_* magic env vars so Coolify auto-wires Traefik labels
-#   - Build context is the repository root (Coolify clones the whole repo there)
 
 services:
   web:
     build:
-      context: ..
+      context: .
       dockerfile: docker/Dockerfile.web
     restart: unless-stopped
     environment:
@@ -64,7 +68,7 @@ services:
 
   collab:
     build:
-      context: ..
+      context: .
       dockerfile: docker/Dockerfile.collab
     restart: unless-stopped
     environment:
@@ -91,7 +95,7 @@ services:
   # for future HTTP/SSE transport. Comment the whole block out if not needed.
   mcp:
     build:
-      context: ..
+      context: .
       dockerfile: docker/Dockerfile.mcp
       args:
         MCP_SERVER_PORT: ${MCP_SERVER_PORT:-3001}