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

Pages/Groups.razor

@@ -57,7 +57,7 @@
 						placeholder="@Localizer["Invitation code"]" data-group-code>
 					<Prefix><i class="ion-md-key"></i></Prefix>
 				</DInput>
-				<DInput TValue="string" type="password" @bind-Value="joining.InvitationPassword" Immediate="true" autocomplete="current-password" maxlength="128"
+				<DInput TValue="string" type="password" @bind-Value="joining.InvitationPassword" Immediate="true" maxlength="128"
 						placeholder="@Localizer["Invitation password, if it has one"]" />
 				<DButton Type="submit" Size="DSize.Sm" class="self-end" Disabled="@(IsDefaultDisabled || isSaving || string.IsNullOrWhiteSpace(joining.InvitationCode))" data-group-join-submit>
 					<i class="ion-md-log-in"></i><span>@Localizer["Join"]</span>