chore: add devcontainer, CI workflow, and gitignore

Author: jt55401

.devcontainer/devcontainer.json

@@ -0,0 +1,26 @@
+{
+  "name": "HTMLTrust Canonicalization",
+  "image": "mcr.microsoft.com/devcontainers/base:ubuntu",
+  "features": {
+    "ghcr.io/devcontainers/features/node:1": {
+      "version": "22"
+    },
+    "ghcr.io/devcontainers/features/go:1": {
+      "version": "1.23"
+    },
+    "ghcr.io/devcontainers/features/php:1": {
+      "version": "8.3",
+      "installComposer": true
+    }
+  },
+  "postCreateCommand": "cd go && go mod tidy && cd ../php && composer install --no-interaction",
+  "customizations": {
+    "vscode": {
+      "extensions": [
+        "golang.go",
+        "bmewburn.vscode-intelephense-client",
+        "dbaeumer.vscode-eslint"
+      ]
+    }
+  }
+}

.github/workflows/ci.yml

@@ -0,0 +1,82 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  javascript:
+    name: JavaScript
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: "22"
+
+      - name: Run tests
+        working-directory: javascript
+        run: node test.js
+
+      - uses: actions/upload-artifact@v4
+        with:
+          name: javascript-package
+          path: |
+            javascript/index.js
+            javascript/index.d.ts
+            javascript/package.json
+
+  go:
+    name: Go
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-go@v5
+        with:
+          go-version: "1.23"
+
+      - name: Download dependencies
+        working-directory: go
+        run: go mod tidy
+
+      - name: Run tests
+        working-directory: go
+        run: go test -v ./...
+
+      - uses: actions/upload-artifact@v4
+        with:
+          name: go-package
+          path: |
+            go/canonicalize.go
+            go/go.mod
+            go/go.sum
+
+  php:
+    name: PHP
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: shivammathur/setup-php@v2
+        with:
+          php-version: "8.3"
+          extensions: intl, mbstring
+
+      - name: Install dependencies
+        working-directory: php
+        run: composer install --no-interaction --prefer-dist
+
+      - name: Run tests
+        working-directory: php
+        run: composer test
+
+      - uses: actions/upload-artifact@v4
+        with:
+          name: php-package
+          path: |
+            php/src/
+            php/composer.json

.gitignore

@@ -0,0 +1,18 @@
+# OS
+.DS_Store
+Thumbs.db
+
+# Node
+node_modules/
+
+# Go
+go/go.sum
+
+# PHP
+php/vendor/
+php/composer.lock
+
+# IDE
+.idea/
+.vscode/
+*.swp