feat(build): migrate to esbuild application builder

Switch from webpack-based browser builder to esbuild-based application builder. Fix markdown-it default imports, enable esModuleInterop, update polyfills to array format, remove webpack-only options (buildOptimizer, vendorChunk), remove polyfills.ts, and flatten output path to dist/dsomm/.

Author: sawankshrma

angular.json

@@ -15,12 +15,18 @@
       "prefix": "app",
       "architect": {
         "build": {
-          "builder": "@angular-devkit/build-angular:browser",
+          "builder": "@angular-devkit/build-angular:application",
           "options": {
-            "outputPath": "dist/dsomm",
+            "outputPath": {
+              "base": "dist/dsomm",
+              "browser": ""
+            }, 
             "index": "src/index.html",
-            "main": "src/main.ts",
-            "polyfills": "src/polyfills.ts",
+            "browser": "src/main.ts",
+            "polyfills": [
+              "@angular/localize/init",
+              "zone.js"
+            ],
             "tsConfig": "tsconfig.app.json",
             "allowedCommonJsDependencies": [
               "yamljs"
@@ -58,9 +64,7 @@
               "outputHashing": "all"
             },
             "development": {
-              "buildOptimizer": false,
               "optimization": false,
-              "vendorChunk": true,
               "extractLicenses": false,
               "sourceMap": true,
               "namedChunks": true
@@ -90,7 +94,7 @@
           "builder": "@angular-devkit/build-angular:karma",
           "options": {
             "main": "src/test.ts",
-            "polyfills": "src/polyfills.ts",
+            "polyfills": ["zone.js", "zone.js/testing"],
             "tsConfig": "tsconfig.spec.json",
             "karmaConfig": "karma.conf.js",
             "assets": [