feat(settings): add, edit and delete weekly and monthly tasks

They live in Your own, beside the reader's games and events. Every field
has a default the reader can accept unread (weekly, from Monday, ticked
off once) except the target, which nobody can guess for them. Save is
offered only when the store would accept what was typed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

test/custom-ui.test.tsx

@@ -10,6 +10,7 @@ import {
   strandedNotice,
 } from "../src/client/components/CustomForms.tsx";
 import { eventCaption, YourOwn } from "../src/client/components/YourOwn.tsx";
+import { TaskForm, taskDraftFrom } from "../src/client/components/TaskForm.tsx";
 import { EventRow } from "../src/client/components/EventRow.tsx";
 import { EventDetail } from "../src/client/components/EventDetail.tsx";
 import { AUTHOR, Colophon, REPO_URL, RESET_CLOCK_CREDIT } from "../src/client/components/Colophon.tsx";
@@ -1248,3 +1249,65 @@ describe("the index covers events filed under a tracked game", () => {
     expect(html).toContain("ended");
   });
 });
+
+describe("the reader's weekly and monthly tasks in settings", () => {
+  const noop = () => {};
+  const base = {
+    games: GAMES,
+    events: {},
+    lanes: ["zzz", "mygame:limbus-company"],
+    onAddGame: noop,
+    onEditGame: noop,
+    onRemoveGame: () => ({ removed: true, blockedBy: 0 }),
+    onAddEvent: noop,
+    now: Date.parse("2026-10-01T12:00:00.000Z"),
+    onOpen: noop,
+    onAddTask: noop,
+    onEditTask: noop,
+    onRemoveTask: noop,
+  };
+  const task = {
+    id: "mytask:aaaaaa1111", game: "zzz", title: "Activity points",
+    period: { unit: "week" as const, startsOn: 1 },
+    measure: { kind: "amount" as const, target: 2100, unit: "points" },
+    at: AT, updatedAt: AT,
+  };
+
+  test("lists a task with what it asks for", () => {
+    const html = render(<YourOwn {...base} tasks={[task]} />);
+    expect(html).toContain("Activity points");
+    expect(html).toContain("every week from Monday · reach 2,100 points");
+    expect(html).toContain("Add a task");
+  });
+
+  test("with none yet, the way to add one is still there", () => {
+    expect(render(<YourOwn {...base} tasks={[]} />)).toContain("Add a task");
+  });
+
+  test("the form starts weekly, from Monday, ticked off once", () => {
+    const html = render(<TaskForm lanes={["zzz"]} onSave={noop} onCancel={noop} />);
+    expect(html).toMatch(/aria-pressed="true"[^>]*>Every week</);
+    expect(html).toMatch(/<option value="1" selected="">Monday<\/option>/);
+    expect(html).toMatch(/aria-pressed="true"[^>]*>Tick it off</);
+  });
+
+  test("a draft is only valid when the schema would take it", () => {
+    const fields = {
+      game: "zzz", title: "Activity points", unit: "week" as const, weekday: 1, monthDay: 1,
+      kind: "amount" as const, required: "1", target: "2,100", amountUnit: "points",
+    };
+    expect(taskDraftFrom(fields)).toEqual({
+      game: "zzz", title: "Activity points",
+      period: { unit: "week", startsOn: 1 },
+      measure: { kind: "amount", target: 2100, unit: "points" },
+    });
+    expect(taskDraftFrom({ ...fields, title: " " })).toBeNull();
+    expect(taskDraftFrom({ ...fields, target: "" })).toBeNull();
+    expect(taskDraftFrom({ ...fields, kind: "days", required: "9", unit: "month", monthDay: 31 }))
+      .toEqual({
+        game: "zzz", title: "Activity points",
+        period: { unit: "month", startsOn: 31 },
+        measure: { kind: "days", required: 9 },
+      });
+  });
+});