chore: drop unused Default*URL network fields

DefaultRPCURL/DefaultFallbackURL/DefaultFallbackURL2 were only ever populated by the removed embedded-proxy path and are read nowhere, so drop them from the Network struct and the assertions that checked they stayed empty.

Author: friofry

internal/rpc/network/network_test.go

@@ -236,9 +236,6 @@ func (s *NetworkManagerTestSuite) TestLegacyFieldPopulation() {
 	s.Equal("https://direct2.ethereum.io", network.OriginalFallbackURL)
 	s.Equal("https://user1.ethereum.io", network.RPCURL)
 	s.Equal("https://user2.ethereum.io", network.FallbackURL)
-	s.Empty(network.DefaultRPCURL)
-	s.Empty(network.DefaultFallbackURL)
-	s.Empty(network.DefaultFallbackURL2)
 }
 
 func (s *NetworkManagerTestSuite) TestLegacyFieldPopulationWithoutUserProviders() {
@@ -268,9 +265,6 @@ func (s *NetworkManagerTestSuite) TestLegacyFieldPopulationWithoutUserProviders(
 	s.Empty(network.OriginalFallbackURL)                  // No second EmbeddedDirect provider
 	s.Equal("https://direct1.sepolia.io", network.RPCURL) // Defaults to OriginalRPCURL
 	s.Empty(network.FallbackURL)                          // Defaults to OriginalFallbackURL, which is empty
-	s.Empty(network.DefaultRPCURL)
-	s.Empty(network.DefaultFallbackURL)
-	s.Empty(network.DefaultFallbackURL2)
 }
 
 func (s *NetworkManagerTestSuite) TestUpsertNetwork() {

params/network_config.go

@@ -67,9 +67,6 @@ type Network struct {
 
 	// Deprecated fields (kept for backward compatibility)
 	// FIXME: Removal of deprecated fields in integration PR https://github.com/status-im/status-go/pull/6178
-	DefaultRPCURL       string `json:"defaultRpcUrl" validate:"omitempty,url"`       // Deprecated: proxy rpc url
-	DefaultFallbackURL  string `json:"defaultFallbackURL" validate:"omitempty,url"`  // Deprecated: proxy fallback url
-	DefaultFallbackURL2 string `json:"defaultFallbackURL2" validate:"omitempty,url"` // Deprecated: second proxy fallback url
 	RPCURL              string `json:"rpcUrl" validate:"omitempty,url"`              // Deprecated: direct rpc url
 	OriginalRPCURL      string `json:"originalRpcUrl" validate:"omitempty,url"`      // Deprecated: direct rpc url if user overrides RPCURL
 	FallbackURL         string `json:"fallbackURL" validate:"omitempty,url"`         // Deprecated

params/networkdefaults/default_networks_test.go

@@ -64,11 +64,6 @@ func TestBuildDefaultNetworks(t *testing.T) {
 		}
 		require.NoError(t, err)
 
-		// legacy default proxy fields are no longer populated
-		require.Empty(t, n.DefaultRPCURL)
-		require.Empty(t, n.DefaultFallbackURL)
-		require.Empty(t, n.DefaultFallbackURL2)
-
 		// check fallback options
 		if strings.Contains(n.RPCURL, "infura.io") {
 			require.True(t, strings.Contains(n.RPCURL, infuraToken.Reveal()))