perf(oidc): remove get user by ID from jwt profile grant (#8580)

# Which Problems Are Solved

Improve performance by removing a GetUserByID call. The call also
executed a Trigger on projections, which significantly impacted
concurrent requests.

# How the Problems Are Solved

Token creation needs information from the user, such as the resource
owner and access token type.

For client credentials this is solved in a single search. By getting the
user by username (`client_id`), the user details and secret were
obtained in a single query. After that verification and token creation
can proceed. For JWT profile it is a bit more complex. We didn't know
anything about the user until after JWT verification.
The verification did a query for the AuthN key and after that we did a
GetUserByID to get remaining details.

This change uses a joined query when the OIDC library calls the
`GetKeyByIDAndClientID` method on the token storage. The found user
details are set to the verifieer object and returned after verification
is completed.
It is safe because the `jwtProfileKeyStorage` is a single-use object as
a wrapper around `query.Queries`.
This way getting the public key and user details are obtained in a
single query.

# Additional Changes

- Correctly set the `client_id` field with machine's username.

# Additional Context

- Related to: https://github.com/zitadel/zitadel/issues/8352

internal/api/oidc/token_client_credentials.go

@@ -26,15 +26,15 @@ func (s *Server) ClientCredentialsExchange(ctx context.Context, r *op.ClientRequ
 	if err != nil {
 		return nil, err
 	}
-	scope, err = s.checkOrgScopes(ctx, client.user, scope)
+	scope, err = s.checkOrgScopes(ctx, client.resourceOwner, scope)
 	if err != nil {
 		return nil, err
 	}
 
 	session, err := s.command.CreateOIDCSession(ctx,
-		client.user.ID,
-		client.user.ResourceOwner,
-		"",
+		client.userID,
+		client.resourceOwner,
+		client.clientID,
 		scope,
 		domain.AddAudScopeToAudience(ctx, nil, r.Data.Scope),
 		[]domain.UserAuthMethodType{domain.UserAuthMethodTypePassword},