build: convert from webpack to esbuild

.vscode-test.mjs

@@ -0,0 +1,5 @@
+import { defineConfig } from '@vscode/test-cli';
+
+export default defineConfig({
+	files: 'out/test/**/*.test.js',
+});

esbuild.js

@@ -0,0 +1,54 @@
+import { context } from 'esbuild';
+
+const production = process.argv.includes('--production');
+const watch = process.argv.includes('--watch');
+
+async function main() {
+  const ctx = await context({
+    entryPoints: ['src/extension.ts'],
+    bundle: true,
+    format: 'cjs',
+    minify: production,
+    sourcemap: !production,
+    sourcesContent: false,
+    platform: 'node',
+    outfile: 'dist/extension.js',
+    external: ['vscode'],
+    logLevel: 'silent',
+    plugins: [
+      /* add to the end of plugins array */
+      esbuildProblemMatcherPlugin
+    ]
+  });
+  if (watch) {
+    await ctx.watch();
+  } else {
+    await ctx.rebuild();
+    await ctx.dispose();
+  }
+}
+
+/**
+ * @type {import('esbuild').Plugin}
+ */
+const esbuildProblemMatcherPlugin = {
+  name: 'esbuild-problem-matcher',
+
+  setup(build) {
+    build.onStart(() => {
+      console.log('[watch] build started');
+    });
+    build.onEnd(result => {
+      result.errors.forEach(({ text, location }) => {
+        console.error(`✘ [ERROR] ${text}`);
+        console.error(`    ${location.file}:${location.line}:${location.column}:`);
+      });
+      console.log('[watch] build finished');
+    });
+  }
+};
+
+main().catch(e => {
+  console.error(e);
+  process.exit(1);
+});