Refactor watch.js

Switched to BrowserSync's recommended post-2.0.0 syntax.

Organized logic into functions for easier reading.

Add support for customizing the BrowserSync server from 'loconfig.json'.

Example:

```json
"server": {
    "open": true,
    "https": {
        "key": "~/.config/valet/Certificates/{% paths.url %}.key",
        "cert": "~/.config/valet/Certificates/{% paths.url %}.crt"
    }
}
```

build/watch.js

@@ -3,46 +3,12 @@ import concatFiles, { developmentConcatFilesArgs } from './tasks/concats.js';
 import compileScripts, { developmentScriptsArgs } from './tasks/scripts.js';
 import compileStyles, { developmentStylesArgs } from './tasks/styles.js' ;
 import compileSVGs, { developmentSVGsArgs } from './tasks/svgs.js';
+import message from './utils/message.js';
+import notification from './utils/notification.js';
 import resolve from './utils/template.js';
-import server from 'browser-sync';
+import browserSync from 'browser-sync';
 import { join } from 'node:path';
 
-const { paths, tasks } = loconfig;
-
-// Convert view(s) to an array
-switch (typeof paths.views) {
-    case 'string':
-        paths.views = [ paths.views ];
-        break;
-
-    case 'object':
-        if (paths.views == null) {
-            paths.views = [];
-        } else if (!Array.isArray(paths.views)) {
-            paths.views = Object.values(paths.views);
-        }
-        break;
-}
-
-const serverConfig = {
-    open: false,
-    notify: false
-};
-
-// Resolve the URI for the Browsersync server
-if (typeof paths.url === 'string' && paths.url.length > 0) {
-    // Use proxy
-    serverConfig.proxy = paths.url;
-} else {
-    // Use base directory
-    serverConfig.server = {
-        baseDir: paths.dest
-    };
-}
-
-// Start the Browsersync server
-server.init(serverConfig);
-
 // Build scripts, compile styles, concat files,
 // and generate spritesheets on first hit
 concatFiles(...developmentConcatFilesArgs);
@@ -50,10 +16,40 @@ compileScripts(...developmentScriptsArgs);
 compileStyles(...developmentStylesArgs);
 compileSVGs(...developmentSVGsArgs);
 
+// Create a new BrowserSync instance
+const server = browserSync.create();
+
+// Start the BrowserSync server
+server.init(createServerOptions(loconfig), (err) => {
+    if (err) {
+        message('Error starting development server', 'error');
+        message(err);
+
+        notification({
+            title:   'Development server failed',
+            message: `${err.name}: ${err.message}`
+        });
+    }
+});
+
+configureServer(server, loconfig);
+
+/**
+ * Configures the BrowserSync options.
+ *
+ * @param  {BrowserSync} server         - The BrowserSync API.
+ * @param  {object}      loconfig       - The project configset.
+ * @param  {object}      loconfig.paths - The paths options.
+ * @param  {object}      loconfig.tasks - The tasks options.
+ * @return {void}
+ */
+function configureServer(server, { paths, tasks }) {
+    const views = createViewsArray(paths.views);
+
     // Reload on any changes to views or processed files
     server.watch(
         [
-        ...paths.views,
+            ...views,
             join(paths.scripts.dest, '*.js'),
             join(paths.styles.dest, '*.css'),
             join(paths.svgs.dest, '*.svg'),
@@ -98,3 +94,64 @@ server.watch(
     ).on('change', () => {
         compileSVGs(...developmentSVGsArgs);
     });
+}
+
+/**
+ * Creates a new object with all the BrowserSync options.
+ *
+ * @param  {object} loconfig        - The project configset.
+ * @param  {object} loconfig.paths  - The paths options.
+ * @param  {object} loconfig.server - The server options.
+ * @return {object} Returns the server options.
+ */
+function createServerOptions({
+    paths,
+    server: options
+}) {
+    const config = {
+        open: false,
+        notify: false
+    };
+
+    // Resolve the URI for the BrowserSync server
+    if (typeof paths.url === 'string' && paths.url.length > 0) {
+        // Use proxy
+        config.proxy = paths.url;
+    } else if (typeof paths.dest === 'string' && paths.dest.length > 0) {
+        // Use base directory
+        config.server = {
+            baseDir: paths.dest
+        };
+    }
+
+    Object.assign(config, resolve(options));
+
+    return config;
+}
+
+/**
+ * Creates a new array (shallow-copied) from the views configset.
+ *
+ * @param  {*} views - The views configset.
+ * @throws {TypeError} If views is invalid.
+ * @return {array} Returns the views array.
+ */
+function createViewsArray(views) {
+    if (Array.isArray(views)) {
+        return Array.from(views);
+    }
+
+    switch (typeof views) {
+        case 'string':
+            return [ views ];
+
+        case 'object':
+            if (views != null) {
+                return Object.values(views);
+            }
+    }
+
+    throw new TypeError(
+        'Expected \'views\' to be a string, array, or object'
+    );
+}