feat(12.1-02): password and form-only fields, rules per operation and preset

- pact.FormVirtualFields lists form fields that are not model columns: never
  bound, filled or projected; their values reach the Form hooks through
  cabana.VirtualFieldsFromContext when the field's context allows the operation
- type: password is a masked field that must be listed as virtual
- pact.FormRules supplies the rule set per operation and replaces the model's
  Rules() for admin saves; a rule on a virtual field sees the submitted value
- preset on a text field follows another text field on the create form
- SPA: PasswordField, preset handling in FormView, empty password left out of
  an update
- README, docs, OpenAPI document, TS types and dist updated

admin/src/views/FormView.vue

@@ -23,6 +23,7 @@ import {
   focusField,
   initialValues,
   panelDomId,
+  presetValue,
   snapshot,
   tabDomId,
   tabOf,
@@ -162,15 +163,17 @@ const dirty = computed(
     !loading.value &&
     (pendingChanges.value > 0 ||
       activeUploads.value > 0 ||
-      snapshot(editablePayload(fields.value, values.value)) !== saved.value),
+      snapshot(editablePayload(fields.value, values.value, mode)) !== saved.value),
 )
 
 function adopt(record: RecordEnvelope | undefined): void {
   if (record) {
+    // A record response never carries a password, so every password field
+    // is empty again after a save (UI-SPEC S7).
     values.value = { ...record.data }
     labels.value = record.meta.labels ?? {}
   }
-  saved.value = snapshot(editablePayload(fields.value, values.value))
+  saved.value = snapshot(editablePayload(fields.value, values.value, mode))
 }
 
 async function load(): Promise<void> {
@@ -197,8 +200,22 @@ async function load(): Promise<void> {
   loading.value = false
 }
 
+// Preset fields (fields.yaml `preset`, UI-SPEC S7): on create, a text field
+// follows its source field until the administrator edits it by hand; that
+// stops it for as long as the form is open. On update nothing follows.
+const edited = new Set<string>()
+
 function update(name: string, value: unknown): void {
-  values.value = { ...values.value, [name]: value }
+  const next = { ...values.value, [name]: value }
+  edited.add(name)
+  if (mode === 'create') {
+    for (const field of fields.value) {
+      if (field.preset?.field === name && field.type === 'text' && !edited.has(field.name)) {
+        next[field.name] = presetValue(field.preset.type, value)
+      }
+    }
+  }
+  values.value = next
   if (errors.value[name]) {
     const next = { ...errors.value }
     delete next[name]
@@ -255,7 +272,7 @@ async function save(): Promise<RecordEnvelope | null> {
   busy.value = true
   forbidden.value = null
   try {
-    const body = editablePayload(fields.value, values.value)
+    const body = editablePayload(fields.value, values.value, mode)
     const result =
       recordId === null
         ? await api.POST('/{vendor}/{plugin}/{controller}', { params: { path, header: sessionHeader }, body })