a2b2d3fb31
Addresses the maintainer's non-blocking review items + the Outlook email bug:
- invoice create: verify the chosen event belongs to the customer (only when
the event has assignments; legacy unassigned events pass through).
- mark-paid + import: bound paidAt to [2000-01-01, now+30d] so a typo'd year
can't silently drop a payment out of every cash-basis revenue window.
- customer routes: country_code now {min:2,max:2}+isAlpha+uppercase-normalize
(was isString/max:2 — allowed '', '1', '!@'), matching the business-profile
route.
- email transporter: close the previous instance before re-init (leak guard
for a future pooled transport).
- scheduled-email tz: warn loudly when business_hours is set but the profile
timezone is blank (was silently using the server/UTC tz).
- wrapEmailHtml: rebuild the chrome as inline-styled tables + bgcolor and
inline the themed CTA button, so the design survives Outlook/Apple Mail
stripping the head <style> (kept the <style> as progressive enhancement).