Add OIDC login support to compliance page

Add Google and Microsoft sign-in buttons to the trust center connect
page, matching the console sign-in experience. The backend OIDC flow
already supports flexible continue URLs, so only the GraphQL schema
and frontend needed changes.

Signed-off-by: Bryan Frimin <bryan@getprobo.com>

pkg/server/api/trust/v1/schema.graphql

@@ -880,10 +880,18 @@ type RecordSigningEventPayload {
   success: Boolean!
 }
 
+type OIDCProviderInfo {
+  name: String!
+  loginURL: String!
+}
+
 type Query {
   viewer: Identity
   node(id: ID!): Node
   currentTrustCenter: TrustCenter
+  oidcProviders: [OIDCProviderInfo!]!
+    @goField(forceResolver: true)
+    @session(required: OPTIONAL)
 }
 
 type Mutation {

pkg/server/api/trust/v1/v1_resolver.go

@@ -11,6 +11,7 @@ import (
 	"errors"
 	"fmt"
 	"net"
+	"strings"
 	"time"
 
 	"go.gearno.de/kit/log"
@@ -993,6 +994,22 @@ func (r *queryResolver) CurrentTrustCenter(ctx context.Context) (*types.TrustCen
 	return response, nil
 }
 
+// OidcProviders is the resolver for the oidcProviders field.
+func (r *queryResolver) OidcProviders(ctx context.Context) ([]*types.OIDCProviderInfo, error) {
+	providers := r.iam.OIDCService.EnabledProviders()
+	result := make([]*types.OIDCProviderInfo, 0, len(providers))
+
+	for _, p := range providers {
+		name := strings.ToLower(p.String())
+		result = append(result, &types.OIDCProviderInfo{
+			Name:     name,
+			LoginURL: r.baseURL.WithPath("/api/connect/v1/oidc/" + name + "/login").MustString(),
+		})
+	}
+
+	return result, nil
+}
+
 // IsUserAuthorized is the resolver for the isUserAuthorized field.
 func (r *reportResolver) IsUserAuthorized(ctx context.Context, obj *types.Report) (bool, error) {
 	trustService := r.TrustService(ctx, obj.ID.TenantID())