Start from just protos in core.grpc (#5243)

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dotnet/AutoGen.sln

@@ -116,6 +116,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "HelloAgent", "samples\Hello
 EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Hello", "Hello", "{F42F9C8E-7BD9-4687-9B63-AFFA461AF5C1}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Microsoft.AutoGen.Core.Grpc", "src\Microsoft.AutoGen\Core.Grpc\Microsoft.AutoGen.Core.Grpc.csproj", "{3D83C6DB-ACEA-48F3-959F-145CCD2EE135}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -294,6 +296,12 @@ Global
 		{70A8D4B5-D0A6-4098-A6F3-6ED274B65E7D}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{70A8D4B5-D0A6-4098-A6F3-6ED274B65E7D}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{70A8D4B5-D0A6-4098-A6F3-6ED274B65E7D}.Release|Any CPU.Build.0 = Release|Any CPU
+		{3D83C6DB-ACEA-48F3-959F-145CCD2EE135}.CoreOnly|Any CPU.ActiveCfg = Debug|Any CPU
+		{3D83C6DB-ACEA-48F3-959F-145CCD2EE135}.CoreOnly|Any CPU.Build.0 = Debug|Any CPU
+		{3D83C6DB-ACEA-48F3-959F-145CCD2EE135}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{3D83C6DB-ACEA-48F3-959F-145CCD2EE135}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{3D83C6DB-ACEA-48F3-959F-145CCD2EE135}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{3D83C6DB-ACEA-48F3-959F-145CCD2EE135}.Release|Any CPU.Build.0 = Release|Any CPU
 		{AAD593FE-A49B-425E-A9FE-A0022CD25E3D}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 		{AAD593FE-A49B-425E-A9FE-A0022CD25E3D}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{AAD593FE-A49B-425E-A9FE-A0022CD25E3D}.Release|Any CPU.ActiveCfg = Release|Any CPU
@@ -348,6 +356,7 @@ Global
 		{EAFFE339-26CB-4019-991D-BCCE8E7D33A1} = {F823671B-3ECA-4AE6-86DA-25E920D3FE64}
 		{58AD8E1D-83BD-4950-A324-1A20677D78D9} = {F823671B-3ECA-4AE6-86DA-25E920D3FE64}
 		{70A8D4B5-D0A6-4098-A6F3-6ED274B65E7D} = {CE0AA8D5-12B8-4628-9589-DAD8CB0DDCF6}
+		{3D83C6DB-ACEA-48F3-959F-145CCD2EE135} = {18BF8DD7-0585-48BF-8F97-AD333080CE06}
 		{AAD593FE-A49B-425E-A9FE-A0022CD25E3D} = {F42F9C8E-7BD9-4687-9B63-AFFA461AF5C1}
 		{F42F9C8E-7BD9-4687-9B63-AFFA461AF5C1} = {CE0AA8D5-12B8-4628-9589-DAD8CB0DDCF6}
 	EndGlobalSection