feat: phase 0 foundation — monorepo scaffold, backend, frontend, CI, docker

Establishes the skeleton every later phase builds on: Go+Gin API with
zap logging, /api/healthz, SQLite+goose runner; Vite+React18+TS strict+
Tailwind v4 frontend with bento-mono theme tokens; openapi.yaml driving
a generated TS client; oxlint with vendored anti-slop rules; GitHub CI;
multi-stage Dockerfile -> 33.6MB distroless image; docker compose up
serves the blank board.


Generated with [Devin](https://devin.ai)

Authored By: TDvorak <[email protected]>
Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

.gitignore

@@ -0,0 +1,22 @@
+# deps / builds
+node_modules/
+apps/frontend/dist/
+packages/api-client/dist/
+packages/api-client/src/schema.d.ts
+apps/backend/internal/web/dist/*
+!apps/backend/internal/web/dist/.keep
+!apps/backend/internal/web/dist/index.html
+
+# data / runtime
+data/*
+!data/.keep
+*.db
+*.db-*
+
+# env / secrets
+.env
+.env.*
+
+# misc
+.DS_Store
+coverage/