Bugs: clear compare params on tab change, recover channel live messages after a 429,
observer copy link keeps only region params, route table no longer navigates on region
change with nothing selected, map borders memo on data identity, live overview can't
resurrect a failed query, French relative times, no language write on first visit,
0/0 node locations hidden outside the map, path/signal stats use the shared retry rule.
i18n: node/packet/mesh/observer strings that were still hardcoded after #62.
Cleanup: formatUtc, ACTION_BUTTON_CLASS, observer-stats, useWindowedStats, observer-id;
observer pages use StatCard/Card/Field/Segmented/SearchBar/SelectDropdown; one details
chrome on the stats tabs; comment and translations-guide trims; localStorage stub for
Node 26 in the test setup.
Lands the stacked web PRs #75, #79, #80, #81, #83, #85, #87, #89, #92, #95 and #99 in one squash. Server counterparts #166-#176 are merged. Remaining review items follow in a fix PR.