feat(M0): 工程地基 - Go API + Python 采集骨架 + CI + 数据契约

- api/: Go(chi) 只读 API 骨架, /healthz + 版本化路由(占位), Dockerfile, 单测
- ingestion/: Python 采集/ETL 包骨架, units 单位归一化(纯函数+测试), adapter 协议
- docker-compose.yml: postgres + redis + minio + api
- .github/workflows/ci.yml: Go build/vet/test + Python ruff/pytest
- docs/data-contract.md(两端共享契约) + docs/disclaimer.md(不提供购买声明)
- migrations/ 占位(M1 起填充)

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

.github/workflows/ci.yml

@@ -0,0 +1,45 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+
+jobs:
+  go:
+    name: Go (api)
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: api
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v5
+        with:
+          go-version: "1.23"
+          cache-dependency-path: api/go.sum
+      - name: Verify gofmt
+        run: test -z "$(gofmt -l .)"
+      - run: go vet ./...
+      - run: go build ./...
+      - run: go test ./...
+
+  python:
+    name: Python (ingestion)
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: ingestion
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
+        with:
+          python-version: "3.12"
+      - name: Install
+        run: pip install -e ".[dev]"
+      - name: Ruff lint
+        run: ruff check .
+      - name: Ruff format check
+        run: ruff format --check .
+      - name: Pytest
+        run: pytest -q