admin: activity history filters become a live-apply toolbar

the five-field form with its apply button is gone. one row holds a search-shaped domain field and a client ip field that debounce into the url with enter flushing at once, result segments and a time menu that commit instantly, and a clear that appears only when a filter is active without reflowing the row. presets freeze both absolute bounds at click time so a bookmark describes the same investigation later, custom ranges apply atomically through set range with inline validation, and echo queues keep in-flight commits from clobbering newer typing or newer picks. live mode renders no toolbar, the availability banner became a footer note, previous rows stay visible during refetch, and every control carries a 44px hit target.

admin/src/features/activity/HistoryActivity.tsx

@@ -56,7 +56,8 @@ const styles = stylex.create({
 		lineHeight: "1.25rem",
 		color: colors.textMuted,
 	},
-	refetching: {
+	/** The gap a line standing on its own needs from the block above it. */
+	spacedTop: {
 		marginTop: "0.75rem",
 	},
 	moreButton: {
@@ -81,7 +82,9 @@ export default function HistoryActivity({ search }: { search: ActivitySearch })
 
 	const pages = base.data?.pages ?? [];
 	const rows: QueryRow[] = pages.flatMap((page) => page.queries);
-	const coverage = pages[0]?.coverage;
+	// Only from the settled response. Placeholder pages belong to the previous
+	// filter, and a watermark is a claim about the window being displayed.
+	const coverage = base.isPlaceholderData ? undefined : pages[0]?.coverage;
 	const filterActive = Object.keys(filter).length > 0;
 	// `base.hasNextPage` reads the query state, which is empty while placeholder
 	// data stands in for a filter change; derive the cursor from what is on
@@ -112,16 +115,27 @@ export default function HistoryActivity({ search }: { search: ActivitySearch })
 
 	return (
 		<>
+			{/*
+			 * A quiet line, never a skeleton: the rows on screen stay put while a
+			 * filter change is in flight, so a keystroke must not blank the table
+			 * it is narrowing.
+			 */}
 			{base.isFetching && (
-				<p {...stylex.props(styles.note, styles.refetching)} role="status">
-					Loading…
+				<p {...stylex.props(styles.note, styles.spacedTop)} role="status">
+					Updating…
 				</p>
 			)}
-			{coverage !== undefined && <CoverageNotice coverage={coverage} />}
 			{rows.length === 0 ? (
-				<p {...stylex.props(styles.empty)}>
-					{filterActive ? "No queries match the current filters." : "No queries logged yet."}
-				</p>
+				<>
+					<p {...stylex.props(styles.empty)}>
+						{filterActive ? "No queries match the current filters." : "No queries logged yet."}
+					</p>
+					{coverage !== undefined && (
+						<div {...stylex.props(styles.spacedTop)}>
+							<CoverageNotice coverage={coverage} variant="note" />
+						</div>
+					)}
+				</>
 			) : (
 				<>
 					<div {...stylex.props(styles.tableWrap)}>
@@ -158,6 +172,7 @@ export default function HistoryActivity({ search }: { search: ActivitySearch })
 							Showing {rows.length} {rows.length === 1 ? "query" : "queries"}
 							{hasMore ? "" : " — end of log"}
 						</p>
+						{coverage !== undefined && <CoverageNotice coverage={coverage} variant="note" />}
 						{hasMore && (
 							<button
 								type="button"