feat: hide dotfiles in file explorer (#1516)

* feat: hide dotfiles in file explorer

* refactor: rename to "hidden files" and read flag from store

Rename the explorer dotfile toggle to show-semantics "hidden files"
so copy and code share one cross-platform vocabulary, and stop
prop-drilling the flag now that it lives in the panel store.

- explorerShowHiddenFiles (default true) replaces explorerHideDotFiles;
  i18n keys + translations switched from "dotfiles" to "hidden files"
- imperative helpers read usePanelStore.getState() instead of taking
  the flag as a parameter; flag stays threaded only through the
  reactive tree-row render path
- drop dead usePanelState exposure; collapse migration double-guard

* fix: address Greptile review on hidden-file path matching

- isHiddenExplorerPath no longer treats ".." segments as hidden
  (only "." was exempt before); add tests for ".." and "../sibling"
- assert the showHiddenFiles i18n key alongside hideHiddenFiles

---------

Co-authored-by: Mohamed Boudra <boudra.moha@gmail.com>

packages/app/src/file-explorer/visibility.test.ts

@@ -0,0 +1,44 @@
+import { describe, expect, it } from "vitest";
+import type { ExplorerEntry } from "@/stores/session-store";
+import { filterVisibleExplorerEntries, isHiddenExplorerPath } from "./visibility";
+
+function makeEntry(name: string, kind: ExplorerEntry["kind"]): ExplorerEntry {
+  return {
+    name,
+    path: name,
+    kind,
+    size: 0,
+    modifiedAt: "2026-01-01T00:00:00.000Z",
+  };
+}
+
+describe("file explorer visibility", () => {
+  it("keeps dot-prefixed entries when hidden files are shown", () => {
+    const entries = [makeEntry(".env", "file"), makeEntry("src", "directory")];
+
+    expect(filterVisibleExplorerEntries(entries, true)).toEqual(entries);
+  });
+
+  it("hides dot-prefixed files and directories when hidden files are not shown", () => {
+    const entries = [
+      makeEntry(".env", "file"),
+      makeEntry(".git", "directory"),
+      makeEntry("README.md", "file"),
+      makeEntry("src", "directory"),
+    ];
+
+    expect(filterVisibleExplorerEntries(entries, false).map((entry) => entry.name)).toEqual([
+      "README.md",
+      "src",
+    ]);
+  });
+
+  it("detects paths nested under dot-prefixed directories", () => {
+    expect(isHiddenExplorerPath(".")).toBe(false);
+    expect(isHiddenExplorerPath("..")).toBe(false);
+    expect(isHiddenExplorerPath("../sibling")).toBe(false);
+    expect(isHiddenExplorerPath("src/components")).toBe(false);
+    expect(isHiddenExplorerPath(".git")).toBe(true);
+    expect(isHiddenExplorerPath("src/.cache/output.json")).toBe(true);
+  });
+});

packages/app/src/file-explorer/visibility.ts

@@ -0,0 +1,17 @@
+import type { ExplorerEntry } from "@/stores/session-store";
+
+export function isHiddenExplorerPath(path: string): boolean {
+  return path
+    .split("/")
+    .some((segment) => segment !== "." && segment !== ".." && segment.startsWith("."));
+}
+
+export function filterVisibleExplorerEntries(
+  entries: ExplorerEntry[],
+  showHiddenFiles: boolean,
+): ExplorerEntry[] {
+  if (showHiddenFiles) {
+    return entries;
+  }
+  return entries.filter((entry) => !entry.name.startsWith("."));
+}