fix: CAP compatibility test review fixes (v3.6.49)

Review of v3.6.48 found six issues; the two that matter in use:

- ramProbeParse('') errored, so the basic 'is this CAP compatible with
  this card at all?' run (no overrides) was refused by an alert.  An empty
  list is valid now: the test runs with the CAP's own versions.
- ramCompatVerdict said 'Import list rejected' for every failure.  It now
  distinguishes: a request error (no steps), a failed format probe (the
  card not answering), an INSTALL [for load] refusal, and only then the
  import list - each with its own headline.

Plus:
- the result line shows the applied probe (ramCompatProbeNote: 'probe:
  7 imports -> 0.0 · +1 appended', unmatched AIDs included);
- #ram-compat-block validates 1..240 like the install's block size;
- the server reports probe_unmatched (override AIDs matching no entry,
  previously silent when another override matched) and logs them;
- tests: the endpoint's probe-400 path (a mini CAP + a dummy scc),
  _cap_import_aids, the verdict cases and the probe note.

sw cache simple-v322; tests: 540 Python / 687 Node.

frontend/sw.js

@@ -1,4 +1,4 @@
-const CACHE = 'simple-v321';
+const CACHE = 'simple-v322';
 const URLS = [
   'index.html',
   'help.html',