Phase 0: project scaffold

- Go module + chi server with embedded SPA serving and /api/health
- internal/config env loader (local-dev defaults; auth/copyleaks deferred)
- React 19 + Vite 6 + Tailwind v4 frontend with full Petal design tokens
- Frontend embedded into the binary via web/embed.go (go:embed all:dist)
- README dev workflow, .env.example, BUILD_PLAN progress tracker
- Verified end-to-end: binary serves health, embedded SPA, and SPA fallback

web/embed.go

@@ -0,0 +1,12 @@
+// Package web embeds the built frontend assets so the Go binary can serve them
+// directly (single-binary deployment). The embed path is relative to this file,
+// so it must live alongside the dist/ directory.
+package web
+
+import "embed"
+
+// DistFS holds the built frontend (web/dist). `all:` includes the committed
+// .gitkeep placeholder, so this compiles even before `npm run build` runs.
+//
+//go:embed all:dist
+var DistFS embed.FS