v3.25.6: the PLI dictionary save feedback + the timer wording

The v3.25.5 report's follow-ups: a field the server could not use was
silently dropped, and the PWA also filtered non-hex fields client-side
(never sending them).  The POST now collects them and names them in the
response - `invalid` (a malformed key/value: not hex, an odd number of
digits, a non-string value) and `unknown` (a well-formed code outside the
qualifier list), both omitted when everything was applied - and the PWA's
Save sends every field, composes "Not saved: 0A (invalid value), 18
(unknown qualifier)" (`pysimPliRejectMsg`) into a new #pli-save-msg line
under the button and shows "Not saved" briefly.

The guide's timer exception now says "card-initiated automatic action"
(the timer retries every 5 s; polling/menu are suspended, not retrying).

Docs: api.md's POST contract, help EN/RU - which also said "22 PLI
qualifiers" while the list has 25.  Tests: the rejection lists per case
(odd length, non-hex value/key, non-string, unknown code) and the
valid-save absence, the PWA message helper and the wiring pins.
887 frontend + 875 Python; sw cache simple-v430.

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "pysim-simple-server"
-version = "3.25.5"
+version = "3.25.6"
 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.