chore: add query to fetch top level idp claim fields (#15525)

Adds an api endpoint to grab all available sync field options for IDP
sync. This is for autocomplete on idp sync forms. This is required for
organization admins to have some insight into the claim fields available
when configuring group/role sync.

coderd/database/modelqueries.go

@@ -3,6 +3,7 @@ package database
 import (
 	"context"
 	"database/sql"
+	"encoding/json"
 	"fmt"
 	"strings"
 
@@ -527,3 +528,9 @@ func insertAuthorizedFilter(query string, replaceWith string) (string, error) {
 	filtered := strings.Replace(query, authorizedQueryPlaceholder, replaceWith, 1)
 	return filtered, nil
 }
+
+// UpdateUserLinkRawJSON is a custom query for unit testing. Do not ever expose this
+func (q *sqlQuerier) UpdateUserLinkRawJSON(ctx context.Context, userID uuid.UUID, data json.RawMessage) error {
+	_, err := q.sdb.ExecContext(ctx, "UPDATE user_links SET claims = $2 WHERE user_id = $1", userID, data)
+	return err
+}