feat(ui): Mission Control Recent Sessions mit verschachtelten Handoffs

Neue Tabelle mission_control_sessions (Migration AddMissionControlSessions), befuellt vom
InteractiveLaunchSpecService bei Task-, Ad-hoc- und Handoff-Kacheln. Flyout im Mission-Control-Header
listet die letzten 14 Tage / 50 Sessions, Handoffs eingerueckt unter ihrer Ursprungs-Session, mit
Fortsetzen (--resume im gespeicherten cwd) und Brief anzeigen.

src/ClaudeDo.Data/Migrations/20260928100316_AddMissionControlSessions.cs

@@ -0,0 +1,44 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace ClaudeDo.Data.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddMissionControlSessions : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "mission_control_sessions",
+                columns: table => new
+                {
+                    session_id = table.Column<string>(type: "TEXT", nullable: false),
+                    cwd = table.Column<string>(type: "TEXT", nullable: false),
+                    task_id = table.Column<string>(type: "TEXT", nullable: true),
+                    title = table.Column<string>(type: "TEXT", nullable: false),
+                    started_at = table.Column<DateTime>(type: "TEXT", nullable: false),
+                    predecessor_session_id = table.Column<string>(type: "TEXT", nullable: true),
+                    brief_path = table.Column<string>(type: "TEXT", nullable: true)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_mission_control_sessions", x => x.session_id);
+                });
+
+            migrationBuilder.CreateIndex(
+                name: "IX_mission_control_sessions_started_at",
+                table: "mission_control_sessions",
+                column: "started_at");
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "mission_control_sessions");
+        }
+    }
+}

src/ClaudeDo.Data/Migrations/ClaudeDoDbContextModelSnapshot.cs

@@ -403,6 +403,45 @@ namespace ClaudeDo.Data.Migrations
                     b.ToTable("list_folders", (string)null);
                 });
 
+            modelBuilder.Entity("ClaudeDo.Data.Models.MissionControlSessionEntity", b =>
+                {
+                    b.Property<string>("SessionId")
+                        .HasColumnType("TEXT")
+                        .HasColumnName("session_id");
+
+                    b.Property<string>("BriefPath")
+                        .HasColumnType("TEXT")
+                        .HasColumnName("brief_path");
+
+                    b.Property<string>("Cwd")
+                        .IsRequired()
+                        .HasColumnType("TEXT")
+                        .HasColumnName("cwd");
+
+                    b.Property<string>("PredecessorSessionId")
+                        .HasColumnType("TEXT")
+                        .HasColumnName("predecessor_session_id");
+
+                    b.Property<DateTime>("StartedAt")
+                        .HasColumnType("TEXT")
+                        .HasColumnName("started_at");
+
+                    b.Property<string>("TaskId")
+                        .HasColumnType("TEXT")
+                        .HasColumnName("task_id");
+
+                    b.Property<string>("Title")
+                        .IsRequired()
+                        .HasColumnType("TEXT")
+                        .HasColumnName("title");
+
+                    b.HasKey("SessionId");
+
+                    b.HasIndex("StartedAt");
+
+                    b.ToTable("mission_control_sessions", (string)null);
+                });
+
             modelBuilder.Entity("ClaudeDo.Data.Models.PrimeScheduleEntity", b =>
                 {
                     b.Property<Guid>("Id")