feat(repository): implement user repository (#10967)

## Summary

This PR introduces the relational user repository for backend v3,
including schema, repository APIs, reducers/projections, and tests for
both human and machine users.

## What changed

* Added user-focused relational migrations (users, verifications,
metadata, PATs, machine keys, passkeys, identity provider links) and
related FK wiring.
* Implemented/expanded repository domain contracts and storage
implementations for human and machine user flows.
* Added support for machine secret handling and aligned access token
type modeling.
* Extended user domain models (verifications, password/email/phone/TOTP
state, passkeys, metadata, invite handling, identity provider links).
* Updated projection/reduction coverage and integration tests for key
user lifecycle events.
* Regenerated and updated mocks/enums plus supporting database
change/column utilities.

## Notes for reviewers

* This PR is large because it establishes the foundational relational
user storage layer and related test scaffolding. Sorry for that.

## Closes

Closes #10218
Closes #10224
Closes #10225
Closes #10209
Closes #10802

---------

Co-authored-by: Iraq Jaber <[email protected]>
Co-authored-by: Copilot <[email protected]>
Co-authored-by: Marco A. <[email protected]>
Co-authored-by: Tim Möhlmann <[email protected]>

backend/v3/storage/database/json/json.go

@@ -176,6 +176,7 @@ func NewJsonChanges(col database.Column, changes ...JsonUpdate) database.Change
 	}
 }
 
+// WriteArg implements [gomock.Matcher].
 func (c *jsonChanges) Matches(x any) bool {
 	toMatch, ok := x.(*jsonChanges)
 	if !ok {
@@ -205,10 +206,12 @@ func (c *jsonChanges) Matches(x any) bool {
 	return true
 }
 
+// WriteArg implements [database.Change].
 func (c *jsonChanges) String() string {
 	return "database.json.jsonChange"
 }
 
+// WriteArg implements [database.Change].
 func (c jsonChanges) Write(builder *database.StatementBuilder) error {
 	c.column.WriteUnqualified(builder)
 	builder.WriteString(" = ")
@@ -220,6 +223,12 @@ func (c jsonChanges) Write(builder *database.StatementBuilder) error {
 	return c.changes[len(c.changes)-1].writeUpdate(builder, c, len(c.changes)-2)
 }
 
+// WriteArg implements [database.Change].
 func (c jsonChanges) IsOnColumn(col database.Column) bool {
 	return c.column.Equals(col)
 }
+
+// WriteArg implements [database.Change].
+func (c jsonChanges) WriteArg(builder *database.StatementBuilder) {
+	c.column.WriteArg(builder)
+}