Fix redirect loop by setting NEXT_PUBLIC_ENTE_ALBUMS_ENDPOINT

The app was redirecting to /shared-albums because albumsAppOrigin()
returned the same host as the current URL after runtime replacement.
By setting NEXT_PUBLIC_ENTE_ALBUMS_ENDPOINT at build time to a
placeholder and replacing it at runtime with the full path-based URL,
the host comparison will fail and prevent the redirect loop.

Version bump to 0.3.1

Co-Authored-By: Claude <noreply@anthropic.com>

Dockerfile

@@ -33,6 +33,7 @@ RUN go build -o /build/ente .
 
 FROM node:20-bookworm-slim AS web-builder
 ENV NEXT_PUBLIC_ENTE_ENDPOINT=ENTE_API_ORIGIN_PLACEHOLDER
+ENV NEXT_PUBLIC_ENTE_ALBUMS_ENDPOINT=ENTE_ALBUMS_ORIGIN_PLACEHOLDER
 COPY --from=ente-source /src /ente
 WORKDIR /ente/web
 RUN apt-get update && \