Restore plain print (no save) as the default for /shipping/zpl and /epson/raw

Requiring a name broke the simple 'just print this' API/CI use case --
now that only applies to explicit save/save_and_print, an omitted commit
param (or any other value) just prints, matching how these endpoints
behaved before the Save/Save & Print buttons were added.

app.rb

@@ -220,9 +220,15 @@ end
 post '/shipping/zpl' do
   zpl = params[:zpl].to_s
   name = params[:save_as].to_s
+
   if zpl.strip.empty?
     flash 'ZPL text is empty', 'warning'
-  elsif name.empty?
+    redirect '/upload'
+  end
+
+  case params[:commit]
+  when 'save', 'save_and_print'
+    if name.empty?
       flash 'Name is required to save', 'warning'
     else
       LABEL_REPO.save(name: name, type: 'zpl', content: zpl)
@@ -237,6 +243,16 @@ post '/shipping/zpl' do
         flash "Saved '#{name}'", 'success'
       end
     end
+  else
+    # No explicit save/save_and_print action -- e.g. a plain API/CI call.
+    # labelprint stays a "dumb" print API here: just print, nothing saved.
+    begin
+      print_to_datamax(zpl)
+      flash 'ZPL sent to printer', 'success'
+    rescue => e
+      flash "ZPL print failed (#{e.message})", 'danger'
+    end
+  end
   redirect '/upload'
 end
 
@@ -304,9 +320,15 @@ end
 post '/epson/raw' do
   content = params[:content].to_s
   name = params[:save_as].to_s
+
   if content.strip.empty?
     flash 'Receipt text is empty', 'warning'
-  elsif name.empty?
+    redirect '/epson'
+  end
+
+  case params[:commit]
+  when 'save', 'save_and_print'
+    if name.empty?
       flash 'Name is required to save', 'warning'
     else
       LABEL_REPO.save(name: name, type: 'escpos', content: content)
@@ -321,6 +343,16 @@ post '/epson/raw' do
         flash "Saved '#{name}'", 'success'
       end
     end
+  else
+    # No explicit save/save_and_print action -- e.g. a plain API/CI call.
+    # labelprint stays a "dumb" print API here: just print, nothing saved.
+    begin
+      print_raw_escpos(content)
+      flash 'Sent to Epson printer', 'success'
+    rescue => e
+      flash "Epson print failed (#{e.message})", 'danger'
+    end
+  end
   redirect '/epson'
 end