v4.2.2: validation keeps reproducible findings, /pocs command, version bump

Field feedback: real, reproducible findings (missing HSTS, insecure cookie flags,
internal IP leaked in a header) were being down-rated/dropped by the adversarial
opinion-vote. The user's rule: never discard something real; another person must
be able to reproduce the same finding.

Validation:
- has_http_receipt(): a finding whose proof is a captured HTTP response (status
  line / security headers / Set-Cookie / a header the class is proven by) or a
  file:line citation is REPRODUCIBLE by definition.
- validate(): a finding unanimously rejected by the vote but carrying such a
  receipt is NO LONGER dropped — it is kept as needs-review (capped to what the
  receipt alone proves), because "the response lacks HSTS" is a fact, not a
  story. grounded_receipt() now also recognizes an in-prose HTTP receipt.
- reproducibility: a kept finding at a URL with no explicit repro steps gets a
  minimal pasteable `curl -i` so anyone can reproduce the exact finding.

Also:
- /pocs (aliases /poc /evidence /artifacts): list a run's synthesized/written
  PoC + evidence files with their paths (was: "unknown command /pocs").
- version bumped to 4.2.2 across CLI/clap/web; stale v4.2.1/v4.1.0 labels fixed.

423 tests passing.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

TUTORIAL.md

@@ -1,4 +1,4 @@
-# NeuroSploit — Tutorial & User Guide (v4.2.1)
+# NeuroSploit — Tutorial & User Guide (v4.2.2)
 
 A complete, hands-on guide to installing, configuring and running NeuroSploit —
 the autonomous, multi-model penetration-testing harness.
@@ -100,7 +100,7 @@ Agents **degrade gracefully**: if `rustscan` is absent they use `nmap`; if neith
 ### Verify
 
 ```bash
-neurosploit --version          # neurosploit 4.2.1
+neurosploit --version          # neurosploit 4.2.2
 neurosploit agents             # {"vulns":255,...,"ai":30,...,"total":480}
 neurosploit models             # all providers & models
 ```