Add GitHub Actions workflow to build patched postgres connector JAR

Builds the postgres pipeline connector and publishes it as a GitHub
Release artifact (v3.5.0-patched) on push to patch/** branches.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: cloneot

.github/workflows/build-patched-jar.yml

@@ -0,0 +1,49 @@
+name: Build Patched JAR
+
+on:
+  push:
+    branches:
+      - 'patch/**'
+  workflow_dispatch:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up JDK 8
+        uses: actions/setup-java@v4
+        with:
+          java-version: '8'
+          distribution: 'temurin'
+          cache: maven
+
+      - name: Build postgres connector
+        run: |
+          mvn -pl flink-cdc-connect/flink-cdc-pipeline-connectors/flink-cdc-pipeline-connector-postgres \
+              -am package -DskipTests -q
+
+      - name: Find built JAR
+        id: jar
+        run: |
+          JAR=$(find flink-cdc-connect/flink-cdc-pipeline-connectors/flink-cdc-pipeline-connector-postgres/target \
+                -name 'flink-cdc-pipeline-connector-postgres-*.jar' \
+                ! -name '*-sources.jar' ! -name '*-tests.jar' ! -name '*original*' \
+                | head -1)
+          echo "path=$JAR" >> "$GITHUB_OUTPUT"
+          echo "name=$(basename $JAR)" >> "$GITHUB_OUTPUT"
+
+      - name: Create or update release
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          TAG="v3.5.0-patched"
+          gh release delete "$TAG" --yes 2>/dev/null || true
+          gh release create "$TAG" \
+            --title "v3.5.0-patched" \
+            --notes "Patched flink-cdc-pipeline-connector-postgres with TIMESTAMPTZ fix (FLINK-38742)" \
+            --target "${{ github.sha }}" \
+            "${{ steps.jar.outputs.path }}"