fix(clients): address-proof date fields use calendar picker, Pension Payment Order gets one too

Both the address-proof upload dialog and the permanent-address step used a
native `type="date"` input for the issue/statement date, so no calendar
popup was available. Switched both to Angular Material's datepicker, kept
the client-india-address-step round-trip (payload -> saved description ->
re-parsed on edit) working with the Dates util now that the control holds
a Date object instead of a raw string.

Pension Payment Orders was also the only "Financial & Other" address-proof
type missing requiresDate, so selecting it never showed a date field at
all — added the flag and moved Monthly/Yearly Turnover under the "Other
Income" heading alongside Agriculture/Non-Agriculture Income.

src/app/clients/shared/kyc-proof-types.ts

@@ -145,6 +145,7 @@ export const PROOF_META: Record<string, Partial<ProofType>> = {
   PENSION_PAYMENT_ORDER: {
     sides: 1,
     category: 'Financial & other',
+    requiresDate: true,
     info: 'Pension payment order — upload full document issued by pension authority.'
   },
   CERT_INCORPORATION: {