feat: L0b bootstrap scripts + L1 Go CLI structure

L0b (factory bootstrap):
- bootstrap.ps1 (Windows): pre-checks, interactive config, clone .factory, home.toml
- bootstrap.sh (Linux/Mac): same functionality for bash
- Idempotent re-run with home.toml verification

L1 (Go CLI):
- factory.yaml: manifest schema with components, deps, health-checks
- cmd/factory: Cobra CLI (install/update/status/diagnose)
- pkg/config: home.toml reader
- pkg/manifest: factory.yaml parser + topological sort
- pkg/health: health-check logic (file/dir/mcp_tool/command)

Scripts:
- build.sh: cross-compile for linux/win/darwin × amd64/arm64
- build.ps1: PowerShell cross-compile

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

scripts/build.ps1

@@ -0,0 +1,38 @@
+#!/usr/bin/env pwsh
+# Cross-compile factory for all platforms (Windows-friendly)
+
+$ErrorActionPreference = "Stop"
+$VERSION = if ($env:VERSION) { $env:VERSION } else { "0.1.0" }
+$DIST_DIR = "dist"
+
+Push-Location (Split-Path $PSScriptRoot)
+Write-Host "Building factory v$VERSION..."
+
+New-Item -ItemType Directory -Force -Path $DIST_DIR | Out-Null
+
+$Targets = @(
+    @{ Name = "linux-amd64";  GOOS = "linux";   GOARCH = "amd64" }
+    @{ Name = "linux-arm64";  GOOS = "linux";   GOARCH = "arm64" }
+    @{ Name = "windows-amd64"; GOOS = "windows"; GOARCH = "amd64" }
+    @{ Name = "windows-arm64"; GOOS = "windows"; GOARCH = "arm64" }
+    @{ Name = "darwin-amd64";  GOOS = "darwin";  GOARCH = "amd64" }
+    @{ Name = "darwin-arm64";  GOOS = "darwin";  GOARCH = "arm64" }
+)
+
+foreach ($t in $Targets) {
+    $output = "$DIST_DIR/factory-$($t.GOOS)-$($t.GOARCH)"
+    if ($t.GOOS -eq "windows") { $output += ".exe" }
+
+    Write-Host "  → $($t.Name)"
+
+    $env:GOOS = $t.GOOS
+    $env:GOARCH = $t.GOARCH
+    $env:CGO_ENABLED = "0"
+
+    go build -ldflags="-s -w -X main.Version=$VERSION" -o $output ./cmd/factory
+}
+
+Pop-Location
+
+Write-Host "`n✓ Built to $DIST_DIR/"
+Get-ChildItem $DIST_DIR | Format-Table Name, Length