Add --test CLI filter, docs links in output, and improve probe results page

CLI:
- Add --test option to run specific test IDs (repeatable, case-insensitive)
- Show Expected column and docs URL for each test in console output
- Improve --help descriptions

Website probe results:
- Show language in parentheses after server name in summary and tables
- Sort servers by (pass + warn) combined score
- Show pass + warn breakdown in score column

Also fix:
- pages.yaml: cancel-in-progress to prevent duplicate artifact error
- body/_index.md: "payload body" → "content" (RFC 9112 terminology)
- headers/_index.md: Section 5.1 → 5.2 for obs-fold reference
- README: document --test option with examples

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: MDA2AV

docs/static/probe/render.js

@@ -223,10 +223,12 @@ window.ProbeRender = (function () {
         html += '<div style="height:100%;width:' + failPct + '%;background:' + FAIL_BG + ';transition:width 0.3s;"></div>';
       }
       html += '</div>';
-      // Score: (pass+warn) / total
-      var combined = s.passed + warnings;
-      html += '<div style="min-width:130px;text-align:right;font-size:13px;">';
-      html += '<span style="font-weight:700;color:' + PASS_BG + ';">' + combined + '</span>';
+      // Score: pass + warn / total
+      html += '<div style="min-width:160px;text-align:right;font-size:13px;">';
+      html += '<span style="font-weight:700;color:' + PASS_BG + ';">' + s.passed + '</span>';
+      if (warnings > 0) {
+        html += ' + <span style="font-weight:700;color:' + WARN_BG + ';">' + warnings + '</span>';
+      }
       if (failed > 0) {
         html += ' <span style="color:' + FAIL_BG + ';">' + failed + ' fail</span>';
       }