draggable topology + attack visualizer + tools in containers

- topology nodes draggable (pointer events, SVG transform), layout hint shown
- attack visualizer: /api/attacks logs attacker->target events; red pulsing
  dashed arcs on recent attacks (60s hot), ⚔ counts ok/fail
- submit_flag now takes attacker_idx vs target_idx (A/D semantics); UI has
  target dropdown (enemy teams), leaderboard records target
- containers get vim+curl+wget+netcat+git+pip3 (Dockerfiles blogpost/cdn/
  phew/sheesh/warmup); warmup base ubuntu:20.04 EOL -> 24.04
- team portal: target dropdown refreshed after login (was empty pre-auth)

services/warmup/Dockerfile

@@ -6,14 +6,14 @@ COPY src/main.go .
 RUN go build -o challenge main.go
 
 # Final stage
-FROM public.ecr.aws/docker/library/ubuntu:20.04
+FROM public.ecr.aws/docker/library/ubuntu:24.04
 
 ARG PASSWORD
 
 ENV DEBIAN_FRONTEND=noninteractive
 
 # Install necessary packages
-RUN apt-get update && apt-get install -y nano openssh-server python3 curl netcat-traditional wget sudo nginx golang-go && rm -rf /var/lib/apt/lists/*
+RUN apt-get update && apt-get install -y nano vim git openssh-server python3 curl netcat-traditional wget sudo nginx golang-go && rm -rf /var/lib/apt/lists/*
 
 # Create ctfuser and set password
 RUN useradd -m -d /home/ctfuser ctfuser && echo ctfuser:${PASSWORD} | chpasswd