feat(mvp): phase 1 - project scaffolding & tooling

Initialize SvelteKit project with Svelte 5, TypeScript strict, Tailwind CSS v4,
shadcn-svelte, Prisma + SQLite, Vitest, ESLint, Prettier. Add Docker multi-stage
build, docker-compose, and Gitea Actions CI pipeline.

.env.example

@@ -0,0 +1,22 @@
+# Database
+DATABASE_URL="file:../data/launcher.db"
+
+# Authentication
+JWT_SECRET="change-me-to-a-random-64-char-string"
+JWT_EXPIRY="15m"
+REFRESH_TOKEN_EXPIRY="7d"
+
+# Application
+APP_PORT=3000
+APP_HOST="0.0.0.0"
+APP_URL="http://localhost:3000"
+
+# Guest mode (true = allow unauthenticated dashboard access)
+GUEST_MODE="true"
+
+# Health check interval (cron expression — every 5 minutes)
+HEALTHCHECK_CRON="*/5 * * * *"
+HEALTHCHECK_TIMEOUT_MS="5000"
+
+# Node environment
+NODE_ENV="production"