Initial commit: Phase 1+2 prototype

- Go backend with SQLite, JWT auth, file CRUD
- Vue 3 frontend with split/raw/WYSIWYG editor modes
- Markdown preview (marked, GFM)
- Formatting toolbar + keyboard shortcuts
- File tree with search, create, delete
- Light/dark theme toggle
- Admin panel (user management)
- Preferences (timezone, theme, default mode)
- Shared documents section (placeholder)
- Export: PDF, HTML, MD
- Build daemon (Python, stdlib only)
- Build job queue API
- Docker deployment

Dockerfile

@@ -0,0 +1,28 @@
+FROM node:20-alpine AS frontend
+WORKDIR /app/frontend
+COPY frontend/package.json frontend/package-lock.json* ./
+RUN npm install
+COPY frontend/ .
+RUN npm run build
+
+FROM golang:1.23-alpine AS backend
+WORKDIR /app
+COPY go.mod go.sum ./
+RUN go mod download
+COPY . .
+RUN go build -o /markdownhub ./cmd/server
+RUN go build -o /mdsync ./cmd/mdsync
+
+FROM alpine:3.20
+RUN apk add --no-cache ca-certificates
+WORKDIR /app
+COPY --from=backend /markdownhub /app/markdownhub
+COPY --from=backend /mdsync /app/mdsync
+COPY --from=frontend /app/frontend/dist /app/frontend/dist
+
+ENV MH_DATA_DIR=/app/data
+ENV MH_PORT=8080
+EXPOSE 8080
+VOLUME ["/app/data"]
+
+ENTRYPOINT ["/app/markdownhub"]