fix(wiki): basic conflict detection in CompileReport

Add _detect_conflicts() using adversative keyword heuristic (but,
however, in contrast, …) between chunks of different bibkeys; results
populate CompileReport.conflicts and appear in wiki/log.md.
Also add CompileReport.quarantined field (used by Fix 2).

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

codex/cli.py

@@ -329,6 +329,19 @@ def wiki_check(
             typer.echo(f"⚠ Ungrounded claim(s) in: {page.name}", err=True)
             found_ungrounded = True
 
+    # Check for quarantined pages in wiki/draft/
+    draft_dir = wiki_dir / "draft"
+    draft_pages = sorted(draft_dir.glob("*.md")) if draft_dir.exists() else []
+    if draft_pages:
+        n = len(draft_pages)
+        typer.echo(
+            f"⚠ {n} page(s) quarantined in wiki/draft/ (grounding rate below threshold)",
+            err=True,
+        )
+        for dp in draft_pages:
+            typer.echo(f"  - {dp.name}", err=True)
+        raise typer.Exit(2)
+
     if found_ungrounded:
         raise typer.Exit(1)
     else: