The 1h max-age set in Phase A caused a cache-vs-deploy mismatch when
Phase B refactored config-manager.js to lazy-load admin-overview.js et
al. The new index.html no longer eager-loads those scripts, but
browsers with the cached (pre-Phase-B) config-manager.js didn't do the
lazy-load either — so AdminOverview / AdminSystem / etc. were
undefined and the admin tools rendered 'failed to load' errors.
60s is the right balance: rapid in-session clicks skip the network
round-trip, but a deploy is visible within a minute. ETag-based 304s
still keep the per-request cost tiny when nothing changed.
Signed-off-by: librelad <librelad@digitalangels.vip>
bbae95b504