activity: select-only multi-client filter

the freetype client field is gone. the picker is a select-only menu of known clients with multi-select, chips for the active set, and a 32-client cap shared with the server. the api accepts a comma-separated client list and filters any-of with bound parameters. the trigger carets come from phosphor icons, newly adopted. bundle budget rises to 900000 bytes for the picker and the icon dependency.

admin/src/features/activity/search.ts

@@ -57,6 +57,37 @@ export function validateText(value: unknown): string | undefined {
 	return trimmed === "" ? undefined : trimmed;
 }
 
+/** `queries_repo.max_clients`: past this the API answers 400 rather than filter. */
+export const MAX_CLIENTS = 32;
+
+/**
+ * The client filter: a comma-separated list of exact addresses, canonicalized
+ * here and nowhere else.
+ *
+ * This is the one place the value is read, so it is the one place it can be made
+ * to mean exactly one thing. Everything downstream — the chips that show the
+ * filter and the request that applies it — reads what this returns, so the two
+ * cannot disagree about a link somebody pasted.
+ *
+ * The rule: entries are trimmed, blanks are dropped, repeats are dropped, and
+ * the list is cut to the cap. A blank entry names no client and a repeat asks
+ * for the same client twice, so neither changes which rows come back; dropping
+ * them is not a different filter, it is the same filter written once. The cut is
+ * a different filter, and it is the honest one available: the API refuses a
+ * longer list outright, so keeping the extra addresses would show a filter that
+ * cannot be applied at all.
+ */
+export function validateClients(value: unknown): string | undefined {
+	if (typeof value !== "string") return undefined;
+	const seen = new Set<string>();
+	for (const entry of value.split(",")) {
+		const trimmed = entry.trim();
+		if (trimmed !== "") seen.add(trimmed);
+		if (seen.size === MAX_CLIENTS) break;
+	}
+	return seen.size === 0 ? undefined : [...seen].join(",");
+}
+
 /**
  * The API filter for a validated search, built field by field.
  *
@@ -82,7 +113,7 @@ export function validateActivitySearch(search: Record<string, unknown>): Activit
 		since: validateTimestamp(search["since"]),
 		until: validateTimestamp(search["until"]),
 		domain: validateText(search["domain"]),
-		client: validateText(search["client"]),
+		client: validateClients(search["client"]),
 		blocked: validateBlocked(search["blocked"]),
 	};
 }