fix: manage root CA for LDAP IdPs correctly (#9517)

# Which Problems Are Solved

#9292 did not correctly change the projection table to list IdPs for existing ZITADEL setups.

# How the Problems Are Solved

Fixed the projection table by an explicit setup.

# Additional Changes

To prevent user facing error when using the LDAP with a custom root CA as much as possible, the certificate is parsed when passing it to the API.

# Additional Context

- Closes https://github.com/zitadel/zitadel/issues/9514

---------

Co-authored-by: Iraq Jaber <IraqJaber@gmail.com>
(cherry picked from commit 11c9be3b8d)

internal/command/instance_idp.go

@@ -2,6 +2,7 @@ package command
 
 import (
 	"context"
+	"crypto/x509"
 	"strings"
 
 	"github.com/zitadel/saml/pkg/provider/xml"
@@ -1532,6 +1533,12 @@ func (c *Commands) prepareAddInstanceLDAPProvider(a *instance.Aggregate, writeMo
 		if len(provider.UserFilters) == 0 {
 			return nil, zerrors.ThrowInvalidArgument(nil, "INST-aAx905n", "Errors.Invalid.Argument")
 		}
+		if len(provider.RootCA) > 0 {
+			if err := validateRootCA(provider.RootCA); err != nil {
+				return nil, err
+			}
+		}
+
 		return func(ctx context.Context, filter preparation.FilterToQueryReducer) ([]eventstore.Command, error) {
 			events, err := filter(ctx, writeModel.Query())
 			if err != nil {
@@ -1569,6 +1576,14 @@ func (c *Commands) prepareAddInstanceLDAPProvider(a *instance.Aggregate, writeMo
 	}
 }
 
+func validateRootCA(pemCerts []byte) error {
+	rootCAs := x509.NewCertPool()
+	if ok := rootCAs.AppendCertsFromPEM(pemCerts); !ok {
+		return zerrors.ThrowInvalidArgument(nil, "INST-cwqVVdBwKt", "Errors.Invalid.Argument")
+	}
+	return nil
+}
+
 func (c *Commands) prepareUpdateInstanceLDAPProvider(a *instance.Aggregate, writeModel *InstanceLDAPIDPWriteModel, provider LDAPProvider) preparation.Validation {
 	return func() (preparation.CreateCommands, error) {
 		if writeModel.ID = strings.TrimSpace(writeModel.ID); writeModel.ID == "" {
@@ -1595,6 +1610,11 @@ func (c *Commands) prepareUpdateInstanceLDAPProvider(a *instance.Aggregate, writ
 		if len(provider.UserFilters) == 0 {
 			return nil, zerrors.ThrowInvalidArgument(nil, "INST-aAx901n", "Errors.Invalid.Argument")
 		}
+		if len(provider.RootCA) > 0 {
+			if err := validateRootCA(provider.RootCA); err != nil {
+				return nil, err
+			}
+		}
 		return func(ctx context.Context, filter preparation.FilterToQueryReducer) ([]eventstore.Command, error) {
 			events, err := filter(ctx, writeModel.Query())
 			if err != nil {