switch to miniconda3 base image, add Java via SDKMAN

- Base image: continuumio/miniconda3 (conda + python 3 out of the box)
- Java: installed via SDKMAN (sdk install java) — latest LTS by default
- Node.js: nvm install kept from previous change
- All tool envs (nvm, sdkman) sourced before exec so Python and all
  child processes (exec-tool, jobs) inherit the full PATH

docker-compose.yml

@@ -1,6 +1,6 @@
 services:
   mcp-bash:
-    image: python:3.12-slim
+    image: continuumio/miniconda3:latest
     container_name: mcp-bash
     restart: unless-stopped
     working_dir: /workspace

server/startup.sh

@@ -4,19 +4,34 @@ set -e
 # ─── System packages ──────────────────────────────────────────────────────────
 apt-get update -qq
 apt-get install -y --no-install-recommends \
-    curl wget git vim nano htop procps jq less unzip
+    curl wget git vim nano htop procps jq less unzip zip \
+    build-essential ca-certificates
 
-# ─── Python dependencies ──────────────────────────────────────────────────────
+# ─── Python dependencies (via conda base env) ─────────────────────────────────
 pip install -q -r /app/requirements.txt
 
-# ─── Custom setup (add your own steps below) ──────────────────────────────────
+# ─── Node.js via nvm ──────────────────────────────────────────────────────────
 curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.40.5/install.sh | bash
 
 export NVM_DIR="$HOME/.nvm"
-[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"  # This loads nvm
+[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"
 [ -s "$NVM_DIR/bash_completion" ] && \. "$NVM_DIR/bash_completion"
 
 nvm install 24
 
+# ─── Java via SDKMAN ──────────────────────────────────────────────────────────
+curl -s "https://get.sdkman.io" | bash
+
+export SDKMAN_DIR="$HOME/.sdkman"
+[ -s "$SDKMAN_DIR/bin/sdkman-init.sh" ] && \. "$SDKMAN_DIR/bin/sdkman-init.sh"
+
+sdk install java
+
+# ─── Custom setup (add your own steps below) ──────────────────────────────────
+# Example:
+#   conda install -y pandas numpy
+#   sdk install gradle
+#   npm install -g typescript
+
 # ─── Start server ─────────────────────────────────────────────────────────────
 exec python -u /app/main.py