intelligence: run the chatter classifier before the too-short skip, not after (#127)

82% of the classifier's backtest flags were <=5-word transcripts that already exit at skip_reason=transcript_too_short before the classifier ever ran, so shadow mode was on track to observe roughly a fifth of the real catch rate. Compute the verdict once, ahead of that check, and fold it into whichever doc_set already runs (no extra Firestore write). Also add a chatter_classifier_flagged/reason tally spanning both linked calls AND orphans in admin.py's summary block -- the target population is non-events, which land as orphans or single-call incidents, so linked alone undercounts it the same way corr_gate_veto would have without the #126 fix.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

Claude-Session: https://claude.ai/code/session_01Tbknwttzou4s46PAykmtix

drb-c2-core/app/routers/admin.py

@@ -309,6 +309,17 @@ async def debug_correlation(
         # server-26#115 — this IS the number the escape-hatch fix exists to
         # produce: why each llm=orphan/rules=new call escaped the gate.
         "corr_gate_veto":         _tally(c.get("corr_gate_veto") for c in linked),
+        # server-26#127 — shadow-mode chatter classifier. The target
+        # population is non-events, which land as orphans or single-call
+        # incidents, NOT as a slice of every linked call -- tally `orphans`
+        # too or this undercounts the exact thing the feature measures.
+        "chatter_classifier_flagged": sum(
+            1 for c in (linked + orphans) if c.get("chatter_classifier_verdict")
+        ),
+        "chatter_classifier_reason": _tally(
+            c.get("chatter_classifier_reason") for c in (linked + orphans)
+            if c.get("chatter_classifier_verdict")
+        ),
         # STT coverage: correlation quality is capped by this, so it belongs in
         # the same view rather than a separate investigation.
         "linked_calls_with_transcript": with_transcript,