Web widget product label section and note

This module extends the product label and note field used on invoice lines in the Accounting app. It adds a small eye button next to the description field on each line.

• When the product name is currently shown in the description, the button appears as a crossed-out eye; clicking it removes the product name and keeps only the free-text description.
• When the product name is hidden, the button appears as a normal eye; clicking it puts the product name back at the top of the description.
• The button only appears on editable lines that use the product-and-label column and that already have some description text.

The module also watches the description as you type. If you edit the text while the product name is visible, the product name is automatically kept at the beginning of the description, followed by your text on the next line. If the product name is hidden, your text is saved as-is.

It works together with the standard Accounting product label field and does not add any new menus, models, reports or scheduled actions. It only changes the behaviour of the description field on invoice lines, so users can control whether the product name is repeated in the line description without editing the text manually.