refactor: Modularize build.zsh into separate setup scripts

Separated build.zsh into 3 clear parts:

1. build.zsh (Arch Linux base construction)
   - archiso bootstrap
   - pacstrap base system
   - install base packages
   - install Claude Code

2. cfg/setup-user.sh (User setup)
   - Create ai user
   - Configure sudoers
   - Setup auto-login
   - Configure zshrc and auto-start

3. cfg/setup-claude.sh (Claude/aigpt setup)
   - Install aigpt
   - Configure MCP
   - Setup symlinks
   - Initialize database

Benefits:
- Each file has a single, clear responsibility
- Easier to maintain and modify
- Can skip/customize setup steps if needed
- GitHub Actions simplified to just run build.zsh

cfg/setup-claude.sh

@@ -0,0 +1,56 @@
+#!/bin/bash
+# Claude Code and aigpt setup for aios
+# Installs aigpt, configures MCP, sets up shared memory
+
+ROOTFS="root.x86_64/var/lib/machines/arch"
+
+echo "=== Claude & aigpt Setup ==="
+
+# Install aigpt (AI memory system)
+echo "Installing aigpt..."
+arch-chroot $ROOTFS /bin/sh -c 'git clone https://git.syui.ai/ai/gpt && cd gpt && cargo build --release && cp -rf ./target/release/aigpt /bin/'
+
+# Setup Claude Code MCP configuration (shared via symlink)
+echo "Configuring MCP..."
+# Create actual config in syui/ai/claude (bind-mounted)
+arch-chroot $ROOTFS /bin/sh -c 'mkdir -p /root/.config/syui/ai/claude'
+cat > $ROOTFS/root/.config/syui/ai/claude/claude_desktop_config.json <<'EOF'
+{
+  "mcpServers": {
+    "aigpt": {
+      "command": "aigpt",
+      "args": ["server", "--enable-layer4"]
+    }
+  }
+}
+EOF
+
+# Create symlink for root
+arch-chroot $ROOTFS /bin/sh -c 'ln -sf /root/.config/syui/ai/claude /root/.config/claude'
+
+# Setup for ai user too
+arch-chroot $ROOTFS /bin/sh -c 'mkdir -p /home/ai/.config/syui/ai/claude'
+arch-chroot $ROOTFS /bin/sh -c 'cp /root/.config/syui/ai/claude/claude_desktop_config.json /home/ai/.config/syui/ai/claude/'
+arch-chroot $ROOTFS /bin/sh -c 'ln -sf /home/ai/.config/syui/ai/claude /home/ai/.config/claude'
+arch-chroot $ROOTFS /bin/sh -c 'chown -R ai:ai /home/ai/.config/syui'
+
+# Install ai/bot (optional, for backward compatibility)
+echo "Installing ai/bot..."
+arch-chroot $ROOTFS /bin/sh -c 'git clone https://git.syui.ai/ai/bot && cd bot && cargo build && cp -rf ./target/debug/ai /bin/ && ai ai'
+
+# Create config directory
+arch-chroot $ROOTFS /bin/sh -c 'mkdir -p /root/.config/syui/ai/gpt'
+
+# Copy MCP and aios configuration
+echo "Copying configuration files..."
+cp -rf ./cfg/mcp.json $ROOTFS/root/.config/syui/ai/mcp.json
+cp -rf ./cfg/config.toml $ROOTFS/root/.config/syui/ai/config.toml
+
+# Initialize aigpt database with WAL mode
+echo "Initializing aigpt database..."
+arch-chroot $ROOTFS /bin/sh -c 'aigpt server --enable-layer4 &'
+sleep 2
+arch-chroot $ROOTFS /bin/sh -c 'pkill aigpt'
+arch-chroot $ROOTFS /bin/sh -c 'if command -v sqlite3 &>/dev/null; then sqlite3 /root/.config/syui/ai/gpt/memory.db "PRAGMA journal_mode=WAL; PRAGMA synchronous=NORMAL;"; fi'
+
+echo "✓ Claude & aigpt setup complete"