feat: implement permissions and actions management

- Add permissions logic for status options in corrective actions.
- Create tests for permissions functionality.
- Implement queries for user authentication and actions management.
- Develop Actions page to display and manage corrective actions.
- Create authentication pages for login, setup, and password reset.
- Add IncidentDetail page to view incident details and associated actions.
- Implement Settings page for user management and password changes.

server/lib/dates.ts

@@ -0,0 +1,14 @@
+/** ISO string for a Date, keeping nulls. */
+export const iso = <T extends Date | null>(date: T): T extends Date ? string : string | null => (date ? date.toISOString() : null) as never
+
+/** Calendar date in the server's time zone (set TZ to the plant's zone), e.g. `2026-10-06`. */
+export function localDate(date = new Date()): string {
+  const pad = (value: number) => String(value).padStart(2, '0')
+  return `${date.getFullYear()}-${pad(date.getMonth() + 1)}-${pad(date.getDate())}`
+}
+
+export function addDays(isoDate: string, days: number): string {
+  const date = new Date(`${isoDate}T12:00:00`)
+  date.setDate(date.getDate() + days)
+  return localDate(date)
+}