mara: \"look through the code for dedups, structural improvements
and so on\". Two near-identical blocks across the new-schedule and
edit-schedule forms folded into shared helpers.
## `buildTargetChips({ idPrefix, fieldName, checked, extraNames })`
Was inlined twice in 18-line blocks that built the same
`<label class="schedule-field">` + `<div class="schedule-targets">`
+ candidate-list logic (containers + operator + manager). Now one
function, two callers; `extraNames` lets the edit form keep
showing already-active targets that have vanished from the live
container list so the operator can still uncheck them
intentionally.
## `intervalSecondsFromFormData(fd, namePrefix)`
Both submit handlers had the same ~13-line d/h/m/s → total-seconds
parser (with `NaN` propagation on bad input). Pulled into one
helper next to `buildIntervalComposer`; call sites become 3 lines:
const intervalTotal = intervalSecondsFromFormData(fd, 'interval_');
if (Number.isNaN(intervalTotal)) { alert(...); return; }
const interval_seconds = intervalTotal > 0 ? intervalTotal : null;
Net -13 lines, but the bigger win is shape — when (not if) a new
schedule field surfaces, there's one chip-render path + one
interval-parser to thread it through instead of two.
Zero behaviour change. Built clean.
e8c86bef3b