fix: restore SAFETY/CAPABILITY_CATEGORIES lost in data.py split

Constants were defined in the old monolithic data.py but not carried
over to data/analysis.py during the split, breaking /trends page.

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

src/webui/data/analysis.py

@@ -13,6 +13,10 @@ from sklearn.preprocessing import normalize as sk_normalize
 
 from ietf_analyzer.config import Config
 from ietf_analyzer.db import Database
+
+SAFETY_CATEGORIES = {"AI safety/alignment", "Agent identity/auth", "Policy/governance"}
+CAPABILITY_CATEGORIES = {"A2A protocols", "Agent discovery/reg", "Autonomous netops",
+                         "Data formats/interop", "Human-agent interaction", "Model serving/inference"}
 from webui.data._shared import _cached, _extract_month
 from webui.data.drafts import get_draft_detail