feat(18-01): add the cabana money field (task 1)

- type: money on fields.yaml with currency or currencyFrom, scale (2..4,
  default 4) and max; boot fails naming the field on two sources, none,
  a bad scale or max, a column that is not a string or a Scanner/Valuer,
  or a currencyFrom that is not a string column
- a save answers 422 money.invalid, money.too_precise or money.too_large
  on the field and fills the accepted decimal string unchanged; the same
  check runs on controller, settings and relation child saves
- backend::lang money.* phrases in en and pl
- admin SPA: money.ts (parseMoneyInput, trimMoneyDisplay, formatMoney over
  Intl with the string itself), MoneyField.vue with the currency suffix,
  blur validation and the read-only box, preview through the control,
  the field scope on PreviewView; regenerated OpenAPI and TS types,
  rebuilt modules/boardwalk/dist
- acme.payments fixture with TestMoneyFieldCompile and the Docker
  TestMoneyFieldSmoke; forms.md Money section and cabana README

admin/openapi/admin.json

@@ -1310,6 +1310,14 @@
                     "context": {
                         "$ref": "#/components/schemas/cabana.fieldContext"
                     },
+                    "currency": {
+                        "description": "Currency is the ISO 4217 code a `type: money` field shows as its\nsuffix; exactly one of Currency and CurrencyFrom is set.",
+                        "type": "string"
+                    },
+                    "currencyFrom": {
+                        "description": "CurrencyFrom names the sibling column of the model whose value is the\nmoney field's currency code; the admin follows that field's value.",
+                        "type": "string"
+                    },
                     "default": {
                         "$ref": "#/components/schemas/cabana.jsonScalar"
                     },
@@ -1375,6 +1383,10 @@
                     "label": {
                         "type": "string"
                     },
+                    "max": {
+                        "description": "Max is a money field's column ceiling as a decimal string; a value\nabove it in absolute magnitude is a 422 money.too_large.",
+                        "type": "string"
+                    },
                     "maxDate": {
                         "type": "string"
                     },
@@ -1459,6 +1471,10 @@
                     "required": {
                         "type": "boolean"
                     },
+                    "scale": {
+                        "description": "Scale is the most fraction digits a money value may carry, 2 to 4\n(default 4). A value with more digits is refused, never rounded.",
+                        "type": "integer"
+                    },
                     "size": {
                         "type": "string"
                     },