v3.14.2: the counter probe's verdict rule

The ladder only advances on cntr_low; any other verdict stops the search.
A stop on a non-por_ok verdict after at least one cntr_low keeps the value
anyway - the earlier rejection proves it is above the card's counter - but
the response reports success: false with counter_saved, the verdict and the
saved counter ("something is likely wrong with the security settings");
the PWA shows it amber.  Without a prior cntr_low nothing is saved, and a
missing PoR stays an error.  actual_response_sms_submit/ussd count as
accepted.

Docs: docs/api.md, repo AGENTS.  sw cache simple-v377.
Tests: 672 Python + 798 frontend green.

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "pysim-simple-server"
-version = "3.14.1"
+version = "3.14.2"
 description = "HTTP REST server wrapping pysim for the SIMple PWA"
 requires-python = ">=3.8"
 # pysim is a git-only dependency installed explicitly by setup.bat/setup.sh.