feat: toggle hidden directories in cd-browser with . key

src/app/filesystem.py

@@ -13,28 +13,41 @@ class DirectoryEntry:
     has_children: bool
 
 
-def list_directories(path: Path) -> list[DirectoryEntry]:
+def list_directories(path: Path, show_hidden: bool = False) -> list[DirectoryEntry]:
     """Return direct child directories sorted by name."""
 
     directory_path = path.expanduser().resolve()
     entries: list[DirectoryEntry] = []
 
     for child in directory_path.iterdir():
-        if child.is_dir():
-            entries.append(
-                DirectoryEntry(
-                    name=child.name,
-                    path=child,
-                    has_children=has_subdirectories(child),
-                )
+        if not child.is_dir():
+            continue
+        if not show_hidden and child.name.startswith("."):
+            continue
+
+        entries.append(
+            DirectoryEntry(
+                name=child.name,
+                path=child,
+                has_children=has_subdirectories(child, show_hidden=show_hidden),
             )
+        )
 
     return sorted(entries, key=lambda entry: entry.name.casefold())
 
 
-def has_subdirectories(path: Path) -> bool:
+def has_subdirectories(path: Path, show_hidden: bool = False) -> bool:
     """Return whether the directory contains at least one subdirectory."""
 
     directory_path = path.expanduser().resolve()
 
-    return any(child.is_dir() for child in directory_path.iterdir())
+    for child in directory_path.iterdir():
+        if not child.is_dir():
+            continue
+
+        if not show_hidden and child.name.startswith("."):
+            continue
+
+        return True
+
+    return False