Add workflows

.github/scripts/update_version

@@ -0,0 +1,12 @@
+#!/usr/bin/env bash
+
+if ! git diff --name-only HEAD HEAD~1 | grep -qF 'build.gradle'; then
+  new_version="$(date +%s)"
+  sed --in-place "s!^//version:.*!//version: $new_version!g" build.gradle
+  git add build.gradle
+  git commit -m "[ci skip] update build script version to $new_version"
+  git push
+  printf 'Updated buildscript version to %s\n' "$new_version"
+else
+  printf 'Ignored buildscript version update: no changes detected\n'
+fi

.github/workflows/build-and-test.yml

@@ -0,0 +1,13 @@
+
+name: Build and test
+
+on:
+  pull_request:
+    branches: [ master, main ]
+  push:
+    branches: [ master, main ]
+
+jobs:
+  build-and-test:
+    uses: GTNewHorizons/GTNH-Actions-Workflows/.github/workflows/build-and-test.yml@master
+    secrets: inherit

.github/workflows/release-tags.yml

@@ -0,0 +1,14 @@
+
+name: Release tagged build
+
+on:
+  push:
+    tags: [ '*' ]
+
+permissions:
+  contents: write
+
+jobs:
+  release-tags:
+    uses: GTNewHorizons/GTNH-Actions-Workflows/.github/workflows/release-tags.yml@master
+    secrets: inherit

CODEOWNERS

@@ -0,0 +1,3 @@
+# Any Github changes require admin approval
+/.github/** @GTNewHorizons/admin
+