Two reviewer mutations survived the suite: the web layer routing only a truthy unit (an empty unit then started the bare pick), and the page showing the server's English instead of its own sentence by code. Both are now checked. The bare maint_start comment that said a per-battery unit would ship half a surface is replaced by a pointer to _maint_unit_action(). No behaviour change. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>