Add URL-synced tokenized set-name search to /db/set-list

[Copilot]

/db/set-list had no way to narrow large set lists or preserve filter state in shareable links. This change adds client-side set-name filtering with URL persistence, using AND semantics across space-separated terms.

• Search UI

  • Adds a Search set names input above the set metadata table on /db/set-list.

• Tokenized filtering behavior

  • Filters rows by set name only.
  • Splits the query on whitespace and requires every token to be present in the set name (case-insensitive), so multi-word queries behave as intersection filters.

• URL state synchronization

  • Reads initial query from ?q=... on load and applies it immediately.
  • Updates q via history.replaceState as the user types, enabling reload/share/back-forward with filter state intact.
  • Removes q when the normalized query is empty.

function rowMatchesSearchQuery (row, searchQuery) {
  const setName = row.dataset.setName.toLowerCase();
  const searchTokens = searchQuery.trim().toLowerCase().split(/\s+/).filter(Boolean);
  return searchTokens.every(token => setName.includes(token));
}