net10, the refactor finished, and federation that works

The tree had not compiled since its first commit: Group, DmGroup and
IGroupUsersService were referenced and never written, an IDE rename had
turned the user-settings DTO into the ViewAvatarServer enum, and the settings
were saved as an entity they no longer were.

Built now:
- Group (an ActivityPub Group actor with its own keys, members, invitation
  code and optional password) and DmGroup (a conversation), with
  /clientapi/group/{list,insert,update,join,leave,approve}.
- Posts and DMs: /clientapi/post/{list,insert,delete}, /clientapi/dm/{list,insert};
  DM recipients are local usernames or user@host handles resolved by WebFinger.
- Invitation sign-up and login against the group's invitation code, checking
  the password before any account is created.
- Federation: WebFinger, NodeInfo 2.0, actors at /peasants/{name} (Person,
  Group, and an Application instance actor) with SPKI keys, draft-cavage
  RSA-SHA256 HTTP signatures both ways, an inbox handling Follow (+Accept),
  Undo, Create, Delete and Update, an outbox, notes at /posts/{id}, and a
  persisted, retried, signed delivery queue. A post to a group is announced
  by the group to its followers (FEP-1b12).
- The unused, broken typed ActivityPub models are replaced by a renderer;
  NSign's HMAC setup, which could not federate, is gone.

Upgrade: net10.0, MongoDB.Entities 25.1 (instance DB API, Standard GUIDs),
Swashbuckle 10 / OpenApi 2, Serilog.AspNetCore 10, MailKit 4.18,
PasswordGenerator 3. The JWT keys are 64 bytes (IdentityModel 8 refuses
shorter for HS512). Production runs its own mongod on 127.0.0.1:27022, as
Sintopia's apps do, and deploys to privapub.thepra.dev from the build runner.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012CzABvBkbcFqoHdmi8b9WB

PrivaPub/PrivaPub.csproj

@@ -1,36 +1,20 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
-    <TargetFramework>net7.0</TargetFramework>
+    <TargetFramework>net10.0</TargetFramework>
     <Nullable>disable</Nullable>
     <ImplicitUsings>enable</ImplicitUsings>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="MailKit" Version="4.0.0" />
-    <PackageReference Include="Markdig" Version="0.31.0" />
-    <PackageReference Include="Microsoft.AspNetCore.Authentication.JwtBearer" Version="7.0.5" />
-    <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="7.0.5" />
-    <PackageReference Include="Microsoft.Extensions.Options" Version="7.0.1" />
-    <PackageReference Include="MongoDB.Entities" Version="21.0.2" />
-    <PackageReference Include="NSign.Abstractions" Version="0.16.0" />
-    <PackageReference Include="NSign.AspNetCore" Version="0.16.0" />
-    <PackageReference Include="NSign.Client" Version="0.16.0" />
-    <PackageReference Include="NSign.SignatureProviders" Version="0.16.0" />
-    <PackageReference Include="PasswordGenerator" Version="2.1.0" />
-    <PackageReference Include="Serilog.Extensions.Hosting" Version="5.0.1" />
-    <PackageReference Include="Serilog.Extensions.Logging" Version="3.1.0" />
-    <PackageReference Include="Serilog.Settings.Configuration" Version="3.4.0" />
-    <PackageReference Include="Serilog.Sinks.Console" Version="4.1.0" />
-    <PackageReference Include="Serilog.Sinks.MongoDB" Version="5.3.1" />
-    <PackageReference Include="SshKeyGenerator" Version="1.1.51" />
-    <PackageReference Include="Swashbuckle.AspNetCore" Version="6.5.0" />
-  </ItemGroup>
-
-  <ItemGroup>
-    <Folder Include="Helpers\" />
-    <Folder Include="Services\ServerToServer\" />
-    <Folder Include="Workers\" />
+    <PackageReference Include="MailKit" Version="4.18.0" />
+    <PackageReference Include="Markdig" Version="1.4.0" />
+    <PackageReference Include="Microsoft.AspNetCore.Authentication.JwtBearer" Version="10.0.9" />
+    <PackageReference Include="MongoDB.Entities" Version="25.1.0" />
+    <PackageReference Include="PasswordGenerator" Version="3.0.0" />
+    <PackageReference Include="Serilog.AspNetCore" Version="10.0.0" />
+    <PackageReference Include="Serilog.Sinks.MongoDB" Version="7.3.0" />
+    <PackageReference Include="Swashbuckle.AspNetCore" Version="10.2.3" />
   </ItemGroup>
 
   <ItemGroup>
@@ -52,4 +36,23 @@
     </EmbeddedResource>
   </ItemGroup>
 
+  <Target Name="GenerateBuildInfo" BeforeTargets="BeforeCompile">
+    <PropertyGroup>
+      <BuildInfoPath>$(IntermediateOutputPath)BuildInfo.g.cs</BuildInfoPath>
+    </PropertyGroup>
+    <ItemGroup>
+      <BuildInfoLine Include="public static class BuildInfo" />
+      <BuildInfoLine Include="{" />
+      <BuildInfoLine Include="  public const string Commit = &quot;$(BuildCommit)&quot;%3B" />
+      <BuildInfoLine Include="  public const string Ref = &quot;$(BuildRef)&quot;%3B" />
+      <BuildInfoLine Include="  public const string BuiltAt = &quot;$(BuildTimeUtc)&quot;%3B" />
+      <BuildInfoLine Include="}" />
+    </ItemGroup>
+    <WriteLinesToFile File="$(BuildInfoPath)" Lines="@(BuildInfoLine)" Overwrite="true" WriteOnlyWhenDifferent="true" />
+    <ItemGroup>
+      <Compile Include="$(BuildInfoPath)" />
+      <FileWrites Include="$(BuildInfoPath)" />
+    </ItemGroup>
+  </Target>
+
 </Project>