Every SoundCloud blocker this week fell to looking at the page instead of
reasoning about it, so the probes are kept rather than thrown away — each one
encodes a question worth re-asking when SoundCloud changes its uploader again.

  * `probe_upload_form.py` — enumerate every input/select/textarea/button in the
    upload frame with its label. This produced the whole selector table the
    uploader is written against: #title, #trackPermalink, #artist, #primaryGenre,
    #tags, textarea#description, input#fileInput, and the Upload button.
  * `probe_upload_privacy.py` — read the radio groups properly. Answer: they are
    geo (worldwide/exclusiveRegions/blockedRegions) and licensing
    (all-rights-reserved/commons). NOT privacy.
  * `probe_upload_legacy.py` — does an older, non-v2 uploader still exist with a
    Public/Private choice? Written when I wrongly believed the v2 form had none.
  * `probe_upload_watch.py` — open the real form and poll for state changes, so
    PLN can click a control and have the script report exactly which element it
    is. Built after concluding, twice, that a control was absent.
  * `probe_upload_sharing.py` — drive the MUI Select and VERIFY the trigger
    changed. Confirms Public -> Private end to end.

The lesson the set exists to encode: I reported "the v2 uploader is public-only"
after sweeping every input, select and radio in the frame and finding nothing.
The control was a MUI Select, whose options are portal-rendered only once the
trigger is clicked — so an unmounted menu and an absent feature are
indistinguishable to a DOM sweep. PLN pasted the real markup
(`li[role=option][data-value="Private"]`) and it drove fine first try. A
component library's Select is not `<select>`, and "I searched and found nothing"
is a statement about the search.