[Request] Community 3D model with capacitive filament or capacitative sticker that can be adhered in a corner and app calibrated for the couple grams of weight with 'tare' function

This could also potentially expand the size of items that can be weighed by providing a shim above the wrist rest of the MacBook where larger items could then be placed.

One potential practical use of this I could see is weighing a water bottle periodically to track liquid consumption by placing it on a 3D printed coaster to avoid condensation getting on the trackpad or into the system.

Review the TrackWeight app and the proposed 3D-printed corner accessory first. Clarify the capacitive material, attachment location, supported weight range, calibration flow, and tare behavior before implementation. Done would include a community 3D model and app support for calibrated couple-gram measurements.

Written by the indexing model from the issue text.