[ACA-4715] break dependency on envsubst (#3325)

* remove BPM host

* break dependency on envsubst

* remove prebuild script

* cleanup package.json

app/project.json

@@ -33,9 +33,9 @@
           "app/src/assets",
           "app/src/favicon-96x96.png",
           {
-            "input": "app/.tmp",
-            "output": "/",
-            "glob": "app.config.json"
+            "glob": "app.config.json",
+            "input": "app/src",
+            "output": "/"
           },
           {
             "glob": "**/*",

app/proxy.conf.js

@@ -1,10 +1,10 @@
 require('@alfresco/adf-cli/tooling').dotenvConfig({ path: process.env.ENV_FILE });
 
-const APP_CONFIG_ECM_HOST = process.env.APP_CONFIG_ECM_HOST;
+const { BASE_URL } = process.env;
 
 module.exports = {
     "/alfresco": {
-        "target": APP_CONFIG_ECM_HOST,
+        "target": BASE_URL,
         "secure": false,
         "pathRewrite": {
             "^/alfresco/alfresco": ""
@@ -13,7 +13,7 @@ module.exports = {
         'logLevel': 'debug',
         onProxyReq: function(request) {
           if(request["method"] !== "GET")
-          request.setHeader("origin", APP_CONFIG_ECM_HOST);
+          request.setHeader("origin", BASE_URL);
         },
         // workaround for REPO-2260
         onProxyRes: function (proxyRes) {

app/src/app.config.json

@@ -1,8 +1,8 @@
 {
   "$schema": "../node_modules/@alfresco/adf-core/app.config.schema.json",
-  "ecmHost": "${APP_CONFIG_ECM_HOST}",
-  "aosHost": "${APP_CONFIG_ECM_HOST}/alfresco/aos",
-  "baseShareUrl": "${APP_CONFIG_ECM_HOST}/#/preview/s",
+  "ecmHost": "{protocol}//{hostname}{:port}",
+  "aosHost": "{protocol}//{hostname}{:port}/alfresco/aos",
+  "baseShareUrl": "{protocol}//{hostname}{:port}/#/preview/s",
   "providers": "ECM",
   "authType": "BASIC",
   "loginRoute": "login",