ci: add Makefile and GitHub Actions workflow for PR checks

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: Vova Kolmakov

.github/workflows/flink.yml

@@ -0,0 +1,48 @@
+name: Flink CI
+
+on:
+  push:
+    branches: [main]
+    paths-ignore:
+      - '**.md'
+      - 'docs/**'
+  pull_request:
+    types: [opened, synchronize, ready_for_review, reopened]
+    paths-ignore:
+      - '**.md'
+      - 'docs/**'
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: ${{ github.event_name == 'pull_request' }}
+
+jobs:
+  lint:
+    runs-on: ubuntu-24.04
+    timeout-minutes: 10
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up JDK
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: '8'
+          cache: maven
+      - name: Run lint
+        run: make lint
+
+  build-and-test:
+    runs-on: ubuntu-24.04
+    timeout-minutes: 30
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up JDK
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: '8'
+          cache: maven
+      - name: Install
+        run: make install
+      - name: Test
+        run: make test

Makefile

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+SHELL := /bin/bash
+MAVEN := mvn
+
+.PHONY: install test build bundle clean lint format \
+        install-all test-all build-all help
+
+help:
+	@echo "Available targets:"
+	@echo "  install      Install artifact to local .m2 (skip tests)"
+	@echo "  test         Run unit and integration tests"
+	@echo "  build        Run lint + install"
+	@echo "  bundle       Build shaded fat-jar (skip tests)"
+	@echo "  clean        Remove target/"
+	@echo "  lint         Run Spotless and Checkstyle checks"
+	@echo "  format       Apply Spotless formatting in place"
+	@echo "  install-all  Alias of install (reserved for future multi-module matrix)"
+	@echo "  test-all     Alias of test (reserved for future multi-module matrix)"
+	@echo "  build-all    Alias of build (reserved for future multi-module matrix)"
+
+install:
+	$(MAVEN) install -DskipTests
+
+test:
+	$(MAVEN) test
+
+build:
+	$(MAKE) lint
+	$(MAKE) install
+
+bundle:
+	$(MAVEN) package -DskipTests
+
+clean:
+	$(MAVEN) clean
+
+lint:
+	$(MAVEN) spotless:check checkstyle:check
+
+format:
+	$(MAVEN) spotless:apply
+
+install-all: install
+test-all: test
+build-all: build