feat(FN-3596): unify board/list task ordering, split TaskDetailModal test m

The merge introduces a major TaskDetailModal test refactor (splitting a 6.7K-line monolith into five focused suites), significant merger improvements including autostash race-rescue, deduplication, and advisory logging for destructive operations, a new TUI narrow-mode log-split feature for the dashb

Fusion-Task-Id: FN-3596

packages/dashboard/app/components/taskSorting.ts

@@ -0,0 +1,62 @@
+import type { Task, Column } from "@fusion/core";
+
+function getTaskPriorityRank(priority: Task["priority"] | null | undefined): number {
+  if (priority === "urgent") return 3;
+  if (priority === "high") return 2;
+  if (priority === "low") return 0;
+  return 1;
+}
+
+function compareTaskPriority(a: Task["priority"] | null | undefined, b: Task["priority"] | null | undefined): number {
+  return getTaskPriorityRank(b) - getTaskPriorityRank(a);
+}
+
+function compareTaskIdNumeric(a: string, b: string): number {
+  const aNum = Number.parseInt(a.slice(a.lastIndexOf("-") + 1), 10);
+  const bNum = Number.parseInt(b.slice(b.lastIndexOf("-") + 1), 10);
+
+  if (Number.isFinite(aNum) && Number.isFinite(bNum) && aNum !== bNum) {
+    return aNum - bNum;
+  }
+
+  return a.localeCompare(b);
+}
+
+function getDoneSortTimestamp(task: Task): number {
+  const timestamp = task.columnMovedAt ?? task.updatedAt ?? task.createdAt;
+  const parsed = Date.parse(timestamp);
+  return Number.isFinite(parsed) ? parsed : 0;
+}
+
+function isMergeActiveStatus(status: string | null | undefined): boolean {
+  return status === "merging" || status === "merging-pr" || status === "merging-fix";
+}
+
+export function sortTasksForDisplayColumn(tasks: readonly Task[], column: Column): Task[] {
+  if (column === "todo") {
+    return [...tasks].sort((a, b) => {
+      const priorityCmp = compareTaskPriority(a.priority, b.priority);
+      if (priorityCmp !== 0) return priorityCmp;
+      if (a.createdAt !== b.createdAt) return a.createdAt.localeCompare(b.createdAt);
+      return compareTaskIdNumeric(a.id, b.id);
+    });
+  }
+
+  return [...tasks].sort((a, b) => {
+    if (column === "done") {
+      const timestampCmp = getDoneSortTimestamp(b) - getDoneSortTimestamp(a);
+      if (timestampCmp !== 0) return timestampCmp;
+      return compareTaskIdNumeric(a.id, b.id);
+    }
+
+    if (column === "in-review") {
+      const aIsMerging = isMergeActiveStatus(a.status);
+      const bIsMerging = isMergeActiveStatus(b.status);
+      if (aIsMerging !== bIsMerging) return aIsMerging ? -1 : 1;
+    }
+
+    const priorityCmp = compareTaskPriority(a.priority, b.priority);
+    if (priorityCmp !== 0) return priorityCmp;
+    return compareTaskIdNumeric(a.id, b.id);
+  });
+}