fix(ci): install git+curl in verify-compilation container

The hexpm/elixir slim image lacks git (needed for heroicons git dep)
and curl (needed for esbuild/tailwind binary downloads).

.forgejo/workflows/build.yaml

@@ -60,6 +60,7 @@ jobs:
             docker.io/hexpm/elixir:1.20.1-erlang-29.0.2-debian-trixie-20260518-slim \
             sh -euc '\
               mkdir -p /app && cd /app && tar xf - && \
+              apt-get update -qq && apt-get install -y -qq git curl ca-certificates && \
               mix local.hex --force && \
               mix local.rebar --force && \
               mix deps.get --only prod && \