use jsonify() helper

app.rb

@@ -216,12 +216,13 @@ before do
 end
 
 helpers do
-  def json(obj, opts: nil, pretty: false)
-    if pretty
+  def jsonify(obj, opts: nil, pretty: false)
+    buf = if pretty
       JSON.pretty_generate obj, opts:
     else
       JSON.generate(obj, opts:)
     end
+    "#{buf}\n"
   end
 
   def protected! hidden = false
@@ -251,14 +252,14 @@ end
 get "/env", provides: "json" do
   pretty = params.key? :pretty
 
-  json ENV.sort.to_h, pretty:
+  jsonify ENV.sort.to_h, pretty:
 end
 
 get "/headers", provides: "json" do
   pretty = params.key? :pretty
   h = req_headers
 
-  json h, pretty:
+  jsonify h, pretty:
 end
 
 get "/livez" do
@@ -273,7 +274,7 @@ get "/livez/uptime" do
   tt = TickTock.new
   x = {started_at: tt.started_at, seconds: tt.uptime.to_i, human: human_time(tt.uptime.to_i)}
 
-  json x
+  jsonify x
 end
 
 post "/livez/toggle" do
@@ -337,7 +338,7 @@ end
 get "/pid" do
   pretty = params.key? :pretty
 
-  json({puma: master_pid, pid: Process.pid}, pretty:)
+  jsonify({puma: master_pid, pid: Process.pid}, pretty:)
 end
 
 get "/token" do
@@ -347,31 +348,31 @@ get "/token" do
   token = JWT.encode payload, JWT_SECRET, "HS256"
   x = {token: token, expires_at: expires_at}
 
-  json x
+  jsonify x
 end
 
 get "/token/validate" do
   token = req_headers["authorization"].split[1]
   payload = JWT.decode token, JWT_SECRET, true, algorithm: "HS256"
 
-  json payload
+  jsonify payload
 end
 
 post "/session" do
   session.merge! params
 
-  json session.to_hash
+  jsonify session.to_hash
 end
 
 get "/session" do
   j = session.to_hash
   j[:hostname] = ENV["HOSTNAME"]
 
-  json j
+  jsonify j
 end
 
 get "/cookies" do
-  json response.headers
+  jsonify response.headers
 end
 
 get "/_cat/headers" do
@@ -422,5 +423,5 @@ route :delete, :get, :patch, :post, :put, "/auth/basic", provides: "json" do
     protected!
   end
 
-  json({authenticated: true, user: @auth.username}, pretty:)
+  jsonify({authenticated: true, user: @auth.username}, pretty:)
 end