feat(claude-do): UI-Prozess loggt auf Platte (ui-.log) + fehlgeschlagene Hub-

## Problem
Beim DeleteTask-Bug (Fix 352aaa52) gab es null Spuren: Der UI-Prozess (ClaudeDo.App) hat gar kein File-Logging (weder Serilog noch `Microsoft.Extensions.Logging` sind in App/Ui referenziert), und im Worker loggt SignalR fehlgeschlagene Hub-Invocations nur auf Debug (`Microsoft.AspNetCore` steht in `src/ClaudeDo.Worker/Program.cs` Z. 60 auf Warning). Die Ursache ließ sich nur finden, ind

ClaudeDo-Task: d2ae3831-733f-4d40-93d7-70c93da11590

src/ClaudeDo.Worker/Hub/HubExceptionLoggingFilter.cs

@@ -0,0 +1,27 @@
+using Microsoft.AspNetCore.SignalR;
+using Microsoft.Extensions.Logging;
+
+namespace ClaudeDo.Worker.Hub;
+
+/// <summary>
+/// Logs a Warning for any exception thrown out of a hub method body, so a failed UI action
+/// leaves a trace in <c>worker-.log</c> instead of only a generic error at the caller.
+/// Does NOT see an argument-binding failure (e.g. a stray CancellationToken parameter) — SignalR
+/// rejects those while parsing the invocation message, before a hub method is ever dispatched.
+/// </summary>
+public sealed class HubExceptionLoggingFilter(ILogger<HubExceptionLoggingFilter> logger) : IHubFilter
+{
+    public async ValueTask<object?> InvokeMethodAsync(
+        HubInvocationContext invocationContext, Func<HubInvocationContext, ValueTask<object?>> next)
+    {
+        try
+        {
+            return await next(invocationContext);
+        }
+        catch (Exception ex)
+        {
+            logger.LogWarning(ex, "Hub method {Method} failed", invocationContext.HubMethodName);
+            throw;
+        }
+    }
+}

src/ClaudeDo.Worker/Program.cs

@@ -28,6 +28,7 @@ using ClaudeDo.Worker.Usage.Interfaces;
 using ClaudeDo.Worker.Usage.TokenTracker;
 using ClaudeDo.Worker.Usage.TokenTracker.Interfaces;
 using ClaudeDo.Worker.Worktrees;
+using Microsoft.AspNetCore.SignalR;
 using Microsoft.EntityFrameworkCore;
 using Serilog;
 
@@ -58,6 +59,11 @@ builder.Host.UseSerilog((ctx, lc) => lc
     .MinimumLevel.Information()
     .MinimumLevel.Override("Microsoft.EntityFrameworkCore", Serilog.Events.LogEventLevel.Warning)
     .MinimumLevel.Override("Microsoft.AspNetCore", Serilog.Events.LogEventLevel.Warning)
+    // SignalR logs an argument-binding failure (e.g. a stray CancellationToken parameter, see
+    // fix 352aaa52) at Debug on this specific source context — HubExceptionLoggingFilter can't
+    // see it either, since SignalR rejects the invocation while parsing the message, before any
+    // hub method (and its filter pipeline) is dispatched.
+    .MinimumLevel.Override("Microsoft.AspNetCore.SignalR.Internal.DefaultHubDispatcher", Serilog.Events.LogEventLevel.Debug)
     .WriteTo.File(
         System.IO.Path.Combine(logRoot, "worker-.log"),
         rollingInterval: RollingInterval.Day,
@@ -90,7 +96,11 @@ builder.Services.AddHostedService<UntrackedWorktreeRecovery>();
 // Default MaximumParallelInvocationsPerClient=1 serializes every hub call on one connection —
 // a slow one (e.g. GetTicketProjects hitting an unreachable ticket system) blocks unrelated
 // calls like UpdateList/UpdateListConfig behind it for the same 10s.
-builder.Services.AddSignalR(options => options.MaximumParallelInvocationsPerClient = 10)
+builder.Services.AddSignalR(options =>
+    {
+        options.MaximumParallelInvocationsPerClient = 10;
+        options.AddFilter<HubExceptionLoggingFilter>();
+    })
     .AddJsonProtocol(options =>
     {
         options.PayloadSerializerOptions.Converters.Add(new System.Text.Json.Serialization.JsonStringEnumConverter());