feat: actions v2 for functions (#9420)

# Which Problems Are Solved

Actions v2 are not executed in different functions, as provided by the
actions v1.

# How the Problems Are Solved

Add functionality to call actions v2 through OIDC and SAML logic to
complement tokens and SAMLResponses.

# Additional Changes

- Corrected testing for retrieved intent information
- Added testing for IDP types
- Corrected handling of context for issuer in SAML logic

# Additional Context

- Closes #7247 
- Dependent on https://github.com/zitadel/saml/pull/97
- docs for migration are done in separate issue:
https://github.com/zitadel/zitadel/issues/9456

---------

Co-authored-by: Silvan <27845747+adlerhurst@users.noreply.github.com>

internal/integration/saml.go

@@ -17,6 +17,7 @@ import (
 	"github.com/crewjam/saml"
 	"github.com/crewjam/saml/samlsp"
 	"github.com/zitadel/logging"
+	"github.com/zitadel/saml/pkg/provider"
 
 	http_util "github.com/zitadel/zitadel/internal/api/http"
 	oidc_internal "github.com/zitadel/zitadel/internal/api/oidc"
@@ -220,8 +221,15 @@ func (i *Instance) SuccessfulSAMLAuthRequest(ctx context.Context, userId, id str
 }
 
 func (i *Instance) GetSAMLIDPMetadata() (*saml.EntityDescriptor, error) {
-	idpEntityID := http_util.BuildHTTP(i.Domain, i.Config.Port, i.Config.Secure) + "/saml/v2/metadata"
-	resp, err := http.Get(idpEntityID)
+	issuer := i.Issuer() + "/saml/v2"
+	idpEntityID := issuer + "/metadata"
+
+	req, err := http.NewRequestWithContext(provider.ContextWithIssuer(context.Background(), issuer), http.MethodGet, idpEntityID, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := http.DefaultClient.Do(req)
 	if err != nil {
 		return nil, err
 	}