feat(payment): standalone ZarinPal broker on pay.flatrender.ir

A generic multi-client payment gateway so FlatRender, meezi.ir and
bargevasat.ir can all pay through ZarinPal's single verified callback
domain (pay.flatrender.ir).

New Go service services/payment (clones the notification skeleton +
vendored deps):
- migration 31_payment_broker.sql — `payment` schema: client_apps,
  transactions, webhook_deliveries.
- ZarinPal v4 client ported from the proven identity PaymentService
  (request.json -> StartPay -> verify.json; codes 100/101).
- client API: POST /v1/pay/request + /v1/pay/inquiry, authed by
  X-Api-Key + HMAC body signature; GET /callback/zarinpal (the single
  verified endpoint) verifies, then 302s the user back to the site's
  return_url (signed) and fires a signed, retried webhook.
- per-client ZarinPal merchant override (default = shared merchant);
  amount stored canonically in Rial, unit to ZarinPal env-configurable.
- admin API /v1/admin/* (FlatRender admin JWT): client-app CRUD +
  key issue/rotate + transactions list.

Deploy wiring: payment-svc in docker-compose.v2.yml (host port 1607),
pay.flatrender.ir server block in mirror-nginx conf, ENV_FILE +
README updates (cert SAN + manual migration note).

Admin UI: src/components/admin/PaymentsAdmin.tsx (client apps with
one-time key reveal + rotate, transactions table) + /admin/payments
page + nav link + fa/en strings; pay-admin proxy route to payment-svc.

Docs/SDK: deploy/PAYMENTS.md (integration contract) + deploy/sdk/flatpay.js
(zero-dep Node client + webhook verifier) for meezi/any site.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

services/payment/vendor/github.com/go-playground/locales/currency/currency.go

@@ -0,0 +1,311 @@
+package currency
+
+// Type is the currency type associated with the locales currency enum
+type Type int
+
+// locale currencies
+const (
+	ADP Type = iota
+	AED
+	AFA
+	AFN
+	ALK
+	ALL
+	AMD
+	ANG
+	AOA
+	AOK
+	AON
+	AOR
+	ARA
+	ARL
+	ARM
+	ARP
+	ARS
+	ATS
+	AUD
+	AWG
+	AZM
+	AZN
+	BAD
+	BAM
+	BAN
+	BBD
+	BDT
+	BEC
+	BEF
+	BEL
+	BGL
+	BGM
+	BGN
+	BGO
+	BHD
+	BIF
+	BMD
+	BND
+	BOB
+	BOL
+	BOP
+	BOV
+	BRB
+	BRC
+	BRE
+	BRL
+	BRN
+	BRR
+	BRZ
+	BSD
+	BTN
+	BUK
+	BWP
+	BYB
+	BYN
+	BYR
+	BZD
+	CAD
+	CDF
+	CHE
+	CHF
+	CHW
+	CLE
+	CLF
+	CLP
+	CNH
+	CNX
+	CNY
+	COP
+	COU
+	CRC
+	CSD
+	CSK
+	CUC
+	CUP
+	CVE
+	CYP
+	CZK
+	DDM
+	DEM
+	DJF
+	DKK
+	DOP
+	DZD
+	ECS
+	ECV
+	EEK
+	EGP
+	ERN
+	ESA
+	ESB
+	ESP
+	ETB
+	EUR
+	FIM
+	FJD
+	FKP
+	FRF
+	GBP
+	GEK
+	GEL
+	GHC
+	GHS
+	GIP
+	GMD
+	GNF
+	GNS
+	GQE
+	GRD
+	GTQ
+	GWE
+	GWP
+	GYD
+	HKD
+	HNL
+	HRD
+	HRK
+	HTG
+	HUF
+	IDR
+	IEP
+	ILP
+	ILR
+	ILS
+	INR
+	IQD
+	IRR
+	ISJ
+	ISK
+	ITL
+	JMD
+	JOD
+	JPY
+	KES
+	KGS
+	KHR
+	KMF
+	KPW
+	KRH
+	KRO
+	KRW
+	KWD
+	KYD
+	KZT
+	LAK
+	LBP
+	LKR
+	LRD
+	LSL
+	LTL
+	LTT
+	LUC
+	LUF
+	LUL
+	LVL
+	LVR
+	LYD
+	MAD
+	MAF
+	MCF
+	MDC
+	MDL
+	MGA
+	MGF
+	MKD
+	MKN
+	MLF
+	MMK
+	MNT
+	MOP
+	MRO
+	MRU
+	MTL
+	MTP
+	MUR
+	MVP
+	MVR
+	MWK
+	MXN
+	MXP
+	MXV
+	MYR
+	MZE
+	MZM
+	MZN
+	NAD
+	NGN
+	NIC
+	NIO
+	NLG
+	NOK
+	NPR
+	NZD
+	OMR
+	PAB
+	PEI
+	PEN
+	PES
+	PGK
+	PHP
+	PKR
+	PLN
+	PLZ
+	PTE
+	PYG
+	QAR
+	RHD
+	ROL
+	RON
+	RSD
+	RUB
+	RUR
+	RWF
+	SAR
+	SBD
+	SCR
+	SDD
+	SDG
+	SDP
+	SEK
+	SGD
+	SHP
+	SIT
+	SKK
+	SLL
+	SOS
+	SRD
+	SRG
+	SSP
+	STD
+	STN
+	SUR
+	SVC
+	SYP
+	SZL
+	THB
+	TJR
+	TJS
+	TMM
+	TMT
+	TND
+	TOP
+	TPE
+	TRL
+	TRY
+	TTD
+	TWD
+	TZS
+	UAH
+	UAK
+	UGS
+	UGX
+	USD
+	USN
+	USS
+	UYI
+	UYP
+	UYU
+	UYW
+	UZS
+	VEB
+	VEF
+	VES
+	VND
+	VNN
+	VUV
+	WST
+	XAF
+	XAG
+	XAU
+	XBA
+	XBB
+	XBC
+	XBD
+	XCD
+	XDR
+	XEU
+	XFO
+	XFU
+	XOF
+	XPD
+	XPF
+	XPT
+	XRE
+	XSU
+	XTS
+	XUA
+	XXX
+	YDD
+	YER
+	YUD
+	YUM
+	YUN
+	YUR
+	ZAL
+	ZAR
+	ZMK
+	ZMW
+	ZRN
+	ZRZ
+	ZWD
+	ZWL
+	ZWR
+)