Add web terminal, git credentials, OpenSCAD, review loops, automations

- Web terminal (PTY over WebSocket, xterm.js, sandboxed, reattach with replay)
- Per-user git credentials and commit identity (credential store in the user's home)
- OpenSCAD tool (STL/3MF + preview renders, bounding box) and cad skill; 3D model card
- Craft phase inferred from tool activity when the agent does not report it
- Configurable review loop per mode (rounds, reviewer model, criteria)
- Delete config and Markdown agents from the agent editor
- Automations: cron-scheduled agents from Markdown job files, schedule tool, page
- change_directory tool (only on the user's request)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Dockerfile

@@ -28,6 +28,7 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
         python3 python3-pip python3-venv pipx \
         build-essential pkg-config libssl-dev cmake zlib1g-dev binutils-multiarch \
         chromium fonts-dejavu-core fonts-noto-color-emoji poppler-utils openmpt123 \
+        openscad xvfb xauth \
     && rm -rf /var/lib/apt/lists/*
 # Language servers for diagnostics after edits (rust-analyzer/gopls/clangd can be
 # installed by agents: rustup component add rust-analyzer, go install …).