milestone 29: activity — history, live and policy simulation on one surface

query log, live and lookup merge into /activity. history filters live
in the url, so a pasted link or back/forward reproduces the exact
view; the result column separates servfail and nxdomain from success
in the list. live is follow-by-default with freeze, and a streamed
row opens its in-memory provenance detail — no correlation invented
for rows sqlite has not written. lookup survives as the current
policy simulation under /activity/test. investigation links carry
absolute bounds, and the diagnostics page now honors since/until
instead of ignoring them. the old routes are gone without aliases.

admin/src/shell/AppShell.test.tsx

@@ -7,15 +7,13 @@ import { createAppRouter } from "@/routes";
 
 const NAV_LABELS = [
 	"Dashboard",
-	"Query Log",
-	"Live",
+	"Activity",
 	"Clients",
 	"Groups",
 	"Blocklists",
 	"Rules",
 	"Local DNS",
 	"Upstreams",
-	"Lookup",
 	"Diagnostics",
 	"Settings",
 ];