fix(deadlines): submit only form-managed fields from the deadline form (#1185)

* fix(deadlines): submit only form-managed fields from the deadline form

Fixes #1176. The form fabricated 11 system-field values on every
submit (source: 'user', status: 'upcoming', reminder_offsets,
tax_* nulls, ...) and the edit path PUT the entire merged Deadline
row; only the route handlers' whitelists prevented editing a
system-generated tax deadline from nuking those fields.

The form now has an explicit DeadlineFormValues contract (the 7 fields
it renders), create and edit send exactly that, and the edit handler
takes (id, values) instead of a whole Deadline. No behavior change
today; removes the latent data-loss dependency on the server
whitelist.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* fix(deadlines): migrate calendar DeadlineForm consumers to DeadlineFormValues

The calendar extension's PaymentCalendar (and its CalendarWorkspace
host) still typed the submit chain as the old full-row Omit<Deadline>
shape, failing the core-only typecheck. Behavior unchanged: the raw
insert already omitted ids, and the DB defaults cover system fields.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

components/extensions/general/CalendarWorkspace.tsx

@@ -4,6 +4,7 @@ import { useState, useEffect, useCallback } from 'react'
 import { createClient } from '@/lib/supabase/client'
 import { useToast } from '@/components/ui/use-toast'
 import { PaymentCalendar } from '@/extensions/general/calendar/components/PaymentCalendar'
+import type { DeadlineFormValues } from '@/components/deadlines/DeadlineForm'
 import type { WorkspaceComponentProps } from '@/lib/extensions/workspace-registry'
 import type { Invoice, Deadline } from '@/types'
 
@@ -58,9 +59,7 @@ export default function CalendarWorkspace({ userId }: WorkspaceComponentProps) {
     fetchData()
   }, [fetchData])
 
-  const handleDeadlineCreate = async (
-    data: Omit<Deadline, 'id' | 'user_id' | 'company_id' | 'created_at' | 'updated_at'>
-  ) => {
+  const handleDeadlineCreate = async (data: DeadlineFormValues) => {
     try {
       const { error } = await supabase.from('deadlines').insert([data])