[UX] Add edit functionality to Binning Axes (Measurement Axes) page

[jeandavidt]

Problem

The Binning Axes page (app/pages/8_Binning_Axes.py) has New and Delete buttons but no Edit button. Once a binning axis is created, users cannot modify its name, unit, description, or bin boundaries. This is inconsistent with every other CRUD page in the app (e.g., 3_Campaigns.py, 1_Sites.py).

Acceptance Criteria

• An "Edit Axis" button is available (consistent UI pattern with other pages)
• Edit form allows changing: name, unit, description
• Edit form allows replacing bin boundaries (re-paste custom values or re-generate evenly-spaced)
• A PATCH /binning-axes/{axis_id} (or PUT) API endpoint is added if one does not exist
• The api_client.py has a corresponding update_binning_axis() function

Files to Modify

• app/pages/8_Binning_Axes.py — add Edit button and form dialog
• api/v1/endpoints/binning_axes.py — add PATCH/PUT endpoint
• api/v1/repositories/binning_axis_repository.py — add update query
• app/api_client.py — add update_binning_axis() function