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>

neurosploit-rs/Cargo.toml

@@ -3,7 +3,7 @@ members = ["crates/harness", "app"]
 resolver = "2"
 
 [workspace.package]
-version = "4.2.1"
+version = "4.2.2"
 edition = "2021"
 license = "MIT"
 repository = "https://github.com/JoasASantos/NeuroSploit"