test: coverage for newly extracted pure helpers; document Process/Widget manual verification boundary (#48)

- The new helpers from #43 are now under test
- Added explicit comment explaining that full lifecycle + timing + QML behavior remains manual verification only (no QML test runner exists)

Written by AI agent working for @jtmorris. Model: Grok build-0.1.

test/lib.test.js

@@ -3,6 +3,19 @@ import assert from "node:assert"
 import lib from "../tailscalectl/lib.js"
 const { parsePeers, makeExitNodeCommand, findActiveExitNode, errorMessage, validateClipboardTool, buildCopyCommand, nextClipboardTool, allClipboardTools, buildToggleCommand, parseStatusResult, getStrings, shouldShowClearExitNode, isActiveExitNode } = lib
 
+/*
+ * Test coverage note for #48:
+ * All pure functions exported from lib.js (including the newly extracted
+ * getStrings, shouldShowClearExitNode, isActiveExitNode, and the clipboard
+ * helpers) are exercised here via node:test.
+ *
+ * The four Process objects, 5-second Timer, onExited handlers, copy fallback
+ * state machine, and overall widget behavior in TailscaleWidget.qml have no
+ * automated test coverage. There is no QML test runner in this project.
+ * Those paths are verified manually (see verification checklist in the
+ * feature branch commits).
+ */
+
 test("parsePeers extracts exitNode from ExitNodeOption", () => {
     const peerMap = {
         "peer-1": {