feat: improve agent workspace flows and directory suggestions

packages/app/src/utils/agent-working-directory-suggestions.ts

@@ -0,0 +1,51 @@
+export interface AgentWorkingDirectorySource {
+  cwd?: string | null;
+  createdAt?: Date | null;
+  lastActivityAt?: Date | null;
+}
+
+const PASEO_WORKTREE_PATH_PATTERN = /(^|\/)\.paseo\/worktrees(\/|$)/;
+
+export function collectAgentWorkingDirectorySuggestions(
+  sources: Iterable<AgentWorkingDirectorySource>
+): string[] {
+  const lastSeenByPath = new Map<string, number>();
+
+  for (const source of sources) {
+    const cwd = source.cwd?.trim();
+    if (!cwd) {
+      continue;
+    }
+    if (isPaseoOwnedWorktreePath(cwd)) {
+      continue;
+    }
+
+    const timestamp = toEpochMs(source.lastActivityAt ?? source.createdAt);
+    const previous = lastSeenByPath.get(cwd);
+    if (previous === undefined || timestamp > previous) {
+      lastSeenByPath.set(cwd, timestamp);
+    }
+  }
+
+  return Array.from(lastSeenByPath.entries())
+    .sort((left, right) => {
+      const timeDiff = right[1] - left[1];
+      if (timeDiff !== 0) {
+        return timeDiff;
+      }
+      return left[0].localeCompare(right[0]);
+    })
+    .map(([cwd]) => cwd);
+}
+
+function isPaseoOwnedWorktreePath(cwd: string): boolean {
+  return PASEO_WORKTREE_PATH_PATTERN.test(cwd.replace(/\\/g, "/"));
+}
+
+function toEpochMs(date: Date | null | undefined): number {
+  if (!(date instanceof Date)) {
+    return 0;
+  }
+  const value = date.getTime();
+  return Number.isFinite(value) ? value : 0;
+}