Address review feedback on server mode PR

- Use exit instead of return in document method for consistency
- Replace path.sub regex with delete_prefix in server.rb
- Use to_json for safe JavaScript value embedding

Author: st0012

lib/rdoc/rdoc.rb

@@ -475,7 +475,7 @@ def document(options)
       @store.complete @options.visibility
 
       start_server
-      return
+      exit
     end
 
     unless @options.coverage_report then

lib/rdoc/server.rb

@@ -27,7 +27,7 @@ def self.live_reload_script(last_change_time)
     <<~JS
       <script>
       (function() {
-        var lastChange = #{last_change_time};
+        var lastChange = #{last_change_time.to_json};
         setInterval(function() {
           fetch('/__status').then(function(r) { return r.json(); }).then(function(data) {
             if (data.last_change > lastChange) location.reload();
@@ -196,7 +196,7 @@ def write_response(client, status, content_type, body)
   # Serves a static asset (CSS, JS) from the Aliki template directory.
 
   def serve_asset(path)
-    rel_path = path.sub(%r{\A/}, '')
+    rel_path = path.delete_prefix("/")
     asset_path = File.join(@generator.template_dir, rel_path)
     real_asset = File.expand_path(asset_path)
     real_template = File.expand_path(@generator.template_dir)
@@ -215,7 +215,7 @@ def serve_asset(path)
   # version.
 
   def serve_page(path)
-    name = path.sub(%r{\A/}, '')
+    name = path.delete_prefix("/")
     name = 'index.html' if name.empty?
 
     html = render_page(name)