House rules: numbers through one formatter, no made-up server errors, and the rules fail the build

- Every number shown on a page goes through NumbersExtensions: counts,
  percentages, the nerd readouts and the values written into a style.
- A failure the client builds itself (offline, timeout, retries run out, an
  answer it can't read) is a 400 that names its kind; only a server's own 5XX
  passes through.
- Login, sign-up, recovery and password confirmations leave autocomplete to
  the browser, so it can offer the saved login.
- The Daisy components start with empty lists and attributes, and a
  decorative image still renders alt="".
- Arasaka.HouseRules.Analyzers checks all of this in every build, together
  with PrivaPub.ClientModels.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01W4YtEJrgxG12Pc39Fai8Bd

Directory.Build.props

@@ -0,0 +1,14 @@
+<Project>
+
+  <PropertyGroup>
+    <EnforceCodeStyleInBuild>true</EnforceCodeStyleInBuild>
+    <HouseRulesFormatHelpers>NumbersExtensions</HouseRulesFormatHelpers>
+    <HouseRulesAutocompleteOmit>Login.razor,Join.razor,Setup.razor,PasswordRecovery.razor,AccountEditor.razor,TotpEditor.razor,Groups.razor,ActDialog.razor,BackupsPanel.razor</HouseRulesAutocompleteOmit>
+    <WarningsAsErrors>$(WarningsAsErrors);HR0001;HR0002;HR0003;HR0004;HR0005;HR0006;HR0007;HR0008;HR0009;HR0010;HR0011;HR0101;HR0102;HR0103;HR0104;HR0105;HR0106;HR0201</WarningsAsErrors>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Arasaka.HouseRules.Analyzers" Version="1.0.4" PrivateAssets="all" />
+  </ItemGroup>
+
+</Project>