fix(3.6.8): better Ollama error messages, empty-evidence findings go to needs-review, single-model vote warning

- models.rs: detect connection-refused and timeout on local providers
  (ollama/litellm/llamacpp), show actionable error instead of raw reqwest
- pipeline.rs: findings with empty evidence skip adversarial vote (which
  always rejects per 'default to rejected' prompt) and go straight to
  needs-review for human triage
- pipeline.rs: warn when single-model panel + vote_n=1 (same model
  validates its own findings = weaker validation)
- Bump version 3.6.7 → 3.6.8

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011739wMqPJJPttTLLX6YoQH

neurosploit-rs/Cargo.lock

@@ -871,7 +871,7 @@ dependencies = [
 
 [[package]]
 name = "neurosploit"
-version = "3.6.7"
+version = "3.6.8"
 dependencies = [
  "anyhow",
  "clap",
@@ -888,7 +888,7 @@ dependencies = [
 
 [[package]]
 name = "neurosploit-harness"
-version = "3.6.7"
+version = "3.6.8"
 dependencies = [
  "anyhow",
  "futures",