fix: stop storing code review findings in dashboard, use PR comments only

Code review findings are not actionable in the findings dashboard — they
lack PR context and clutter the list. The PR review pipeline already
posts inline comments directly on PRs (GitHub, Gitea, GitLab), which is
the appropriate place for code review feedback.

- Remove LLM code review stage from the scan pipeline (orchestrator)
- Remove "Code Review" option from the findings type filter dropdown

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

compliance-dashboard/src/pages/findings.rs

@@ -123,7 +123,6 @@ pub fn FindingsPage() -> Element {
                 option { value: "oauth", "OAuth" }
                 option { value: "secret_detection", "Secrets" }
                 option { value: "lint", "Lint" }
-                option { value: "code_review", "Code Review" }
             }
             select {
                 onchange: move |e| { status_filter.set(e.value()); page.set(1); },