feat: add website link to app footer, Join Alpha opens in new tab

Fixes #2 - Add website link to app footer
- Add VITE_WEBSITE_URL build arg for configurable website URL
- Add Git Repository and License links to app footer
- Update Join Free Alpha links to open in new tab (target=_blank)

Dockerfile

@@ -11,12 +11,14 @@ RUN bun build src/index.ts --outdir ./dist --target bun
 
 FROM node:20-alpine AS frontend-builder
 ARG VITE_GIT_URL=https://git.kropa.tech/lotherk/deardiary
+ARG VITE_WEBSITE_URL=https://deardiary.lother.io
 
 WORKDIR /app/frontend
 COPY frontend/package*.json ./
 RUN npm install
 COPY frontend ./
 ENV VITE_GIT_URL=$VITE_GIT_URL
+ENV VITE_WEBSITE_URL=$VITE_WEBSITE_URL
 RUN npm run build
 
 FROM oven/bun:1.1-alpine AS runner