Add uv package manager to base image for on-demand Python support

Install uv from GitHub releases (~23MB). Users can install Python with
'uv python install 3.12' — persists across restarts via devbox-uv volume.
Eliminates need for a separate Python image variant.

README.md

@@ -33,7 +33,8 @@ docker compose run --rm devbox
 - **SSH key forwarding** — git push/pull to private repos
 - **MCP server support** — Node.js included for `npx`-based MCP servers
 - **Non-root user** — runs as `developer` with UID auto-matched to workspace owner (sudo available)
-- **Optional runtimes** — Python, Go via build args (Node.js always included — required for opencode v1.x)
+- **Python via uv** — `uv` package manager included; install Python on demand with `uv python install`
+- **Optional runtimes** — Python (apt), Go via build args (Node.js always included — required for opencode v1.x)
 - **Multi-agent orchestration** — optional [oh-my-opencode-slim](https://github.com/alvinunreal/oh-my-opencode-slim) integration via build arg
 - **AWS CLI v2** — built-in SSO/Bedrock authentication with headless device-code flow
 - **Multi-arch** — amd64 and arm64
@@ -137,6 +138,40 @@ volumes:
   - ~/.config/nvim:/home/developer/.config/nvim:ro
 ```
 
+### Python development with uv
+
+The image includes [uv](https://docs.astral.sh/uv/), a fast Python package manager that replaces pip, venv, and pyenv. Python is not pre-installed but can be installed on demand:
+
+```bash
+# Install Python (persists across restarts with devbox-uv volume)
+uv python install 3.12
+
+# Create a virtual environment and install dependencies
+uv venv
+uv pip install -r requirements.txt
+
+# Or use uv's project workflow (reads pyproject.toml)
+uv sync
+
+# Run a Python script
+uv run python script.py
+
+# Install standalone Python tools
+uvx ruff check .
+```
+
+Python installations are stored in `~/.local/share/uv/`. To persist them across container restarts, add the `devbox-uv` named volume to your `docker-compose.yml`:
+
+```yaml
+volumes:
+  - devbox-uv:/home/developer/.local/share/uv
+
+volumes:
+  devbox-uv:
+```
+
+Project virtual environments (`.venv`) are stored in your workspace directory and persist automatically via the `/workspace` bind mount.
+
 ### Rebuilding the Image
 
 `docker compose run` and `docker compose up` use the existing image — they **do not rebuild** when you change the Dockerfile or build args (e.g. updating `OPENCODE_VERSION`). Rebuild explicitly:
@@ -310,7 +345,7 @@ Container (Debian bookworm)
 ├── opencode binary
 ├── oh-my-opencode-slim (optional — multi-agent orchestration plugin, includes Bun)
 ├── AWS CLI v2 (SSO + Bedrock auth)
-├── neovim 0.12, tmux, htop, bat, eza, zoxide, make
+├── neovim 0.12, tmux, htop, bat, eza, zoxide, uv, make
 ├── git, ssh, ripgrep, fd, fzf, jq, curl, tree
 ├── Node.js (for MCP servers)
 ├── Bun (optional — included with oh-my-opencode-slim)
@@ -326,6 +361,7 @@ Container (Debian bookworm)
 | `/home/developer/.ssh` | Host bind mount (ro) | ✅ Yes | SSH keys |
 | `/home/developer/.aws` | Host bind mount (if configured) | ✅ Yes | AWS credentials/SSO cache |
 | `/home/developer/.local/share/opencode` | Named volume `devbox-data` | ✅ Yes | Session history, memory |
+| `/home/developer/.local/share/uv` | Named volume `devbox-uv` (if configured) | ✅ Yes | Python installs, uv tool installs |
 | `/home/developer/.config/opencode` | Host bind mount (if configured) | ✅ Yes | opencode.json, oh-my-opencode-slim.json, skills |
 
 **opencode config** (`opencode.json`) is auto-generated from `OPENCODE_PROVIDER` on each start. It sets provider and model only — no MCP servers. To persist config changes and use custom settings, mount the config directory from the host (see Custom opencode config above).