Make Weekly Tasks a parent card with individual weeks subordinate to it

Weekly task sheets are pulled out of the flat sidebar list into their own
WEEKLY_TASKS_DATA array. "Weekly Tasks" is now one top-level card among the
track cards; selecting it drills into a breadcrumb view (Weekly Tasks >
Week of...) with a week picker on the left and the selected week's full
detail (table/notes/reports) on the right, using the same buildTaskDetail
renderer as before. Sets up for multiple weeks to coexist cleanly.

index.html

@@ -6314,6 +6314,9 @@
       ],
       reports: []
     },
+  ];
+
+  var WEEKLY_TASKS_DATA = [
     {
       id: "week-2026-08-17",
       label: "Week of 17–21 Aug 2026",
@@ -6334,7 +6337,10 @@
       ]
     }
   ];
+
+  var WEEKLY_TASKS_PARENT_ID = "weekly-tasks-parent";
   var tasksSelectedId = null;
+  var weeklySelectedId = null;
 
   function tasksEsc(s) {
     return String(s == null ? "" : s).replace(/[&<>"]/g, function (c) {
@@ -6344,8 +6350,8 @@
 
   function renderTasksBoard() {
     var sorted = TASKS_DATA; // newest-first order is authored order for now
-    if (!tasksSelectedId || !sorted.some(function (t) { return t.id === tasksSelectedId; })) {
-      tasksSelectedId = sorted.length ? sorted[0].id : null;
+    if (!tasksSelectedId || (tasksSelectedId !== WEEKLY_TASKS_PARENT_ID && !sorted.some(function (t) { return t.id === tasksSelectedId; }))) {
+      tasksSelectedId = sorted.length ? sorted[0].id : WEEKLY_TASKS_PARENT_ID;
     }
 
     var list = document.getElementById("tasks-list");
@@ -6353,10 +6359,71 @@
     sorted.forEach(function (entry) {
       list.appendChild(buildTaskSidebarCard(entry, entry.id === tasksSelectedId));
     });
+    list.appendChild(buildWeeklyParentSidebarCard(tasksSelectedId === WEEKLY_TASKS_PARENT_ID));
 
     var detail = document.getElementById("tasks-detail");
-    var selected = sorted.filter(function (t) { return t.id === tasksSelectedId; })[0];
-    detail.innerHTML = selected ? buildTaskDetail(selected) : "<div class=\"ab-outreach-empty\">No tasks yet.</div>";
+    if (tasksSelectedId === WEEKLY_TASKS_PARENT_ID) {
+      detail.innerHTML = buildWeeklyTasksDrilldown();
+      wireWeeklyDrilldown();
+    } else {
+      var selected = sorted.filter(function (t) { return t.id === tasksSelectedId; })[0];
+      detail.innerHTML = selected ? buildTaskDetail(selected) : "<div class=\"ab-outreach-empty\">No tasks yet.</div>";
+    }
+  }
+
+  function buildWeeklyParentSidebarCard(isSelected) {
+    var card = document.createElement("div");
+    card.className = "ab-card" + (isSelected ? " selected" : "");
+    card.dataset.id = WEEKLY_TASKS_PARENT_ID;
+    card.innerHTML =
+      "<div class=\"ab-card-top\">" +
+        "<div class=\"ab-card-company\">Weekly Tasks</div>" +
+        "<span class=\"ab-source-chip boss\">" + WEEKLY_TASKS_DATA.length + (WEEKLY_TASKS_DATA.length === 1 ? " week" : " weeks") + "</span>" +
+      "</div>" +
+      "<div class=\"ab-card-name\">Peter's weekly task sheets</div>";
+    card.addEventListener("click", function () {
+      tasksSelectedId = WEEKLY_TASKS_PARENT_ID;
+      renderTasksBoard();
+    });
+    return card;
+  }
+
+  function buildWeeklyTasksDrilldown() {
+    if (!weeklySelectedId || !WEEKLY_TASKS_DATA.some(function (w) { return w.id === weeklySelectedId; })) {
+      weeklySelectedId = WEEKLY_TASKS_DATA.length ? WEEKLY_TASKS_DATA[0].id : null;
+    }
+    var selectedWeek = WEEKLY_TASKS_DATA.filter(function (w) { return w.id === weeklySelectedId; })[0];
+
+    var crumbs =
+      "<div class=\"drill-crumbs\">" +
+        "<span class=\"crumb\">Weekly Tasks</span>" +
+        (selectedWeek ? "<span class=\"sep\">/</span><span class=\"crumb current\">" + tasksEsc(selectedWeek.label) + "</span>" : "") +
+      "</div>";
+
+    var weekListHtml = WEEKLY_TASKS_DATA.map(function (w) {
+      return "<div class=\"ab-card" + (w.id === weeklySelectedId ? " selected" : "") + "\" data-week-id=\"" + w.id + "\">" +
+        "<div class=\"ab-card-company\">" + tasksEsc(w.label) + "</div>" +
+      "</div>";
+    }).join("");
+
+    var weekDetailHtml = selectedWeek ? buildTaskDetail(selectedWeek) : "<div class=\"ab-outreach-empty\">No weekly sheets yet.</div>";
+
+    return (
+      crumbs +
+      "<div class=\"ab-outreach\" style=\"display:flex; margin-top:12px;\">" +
+        "<div class=\"ab-outreach-list\" style=\"width:260px;\">" + weekListHtml + "</div>" +
+        "<div class=\"ab-outreach-detail\">" + weekDetailHtml + "</div>" +
+      "</div>"
+    );
+  }
+
+  function wireWeeklyDrilldown() {
+    document.querySelectorAll("#tasks-detail [data-week-id]").forEach(function (el) {
+      el.addEventListener("click", function () {
+        weeklySelectedId = el.getAttribute("data-week-id");
+        renderTasksBoard();
+      });
+    });
   }
 
   function buildTaskSidebarCard(entry, isSelected) {