fix(windows): native Windows correctness for CLI, gateway status, banner, and WSL browser paths

Salvaged from #57016 by @lEWFkRAD:
- cli.py: handle file:///C:/... drive-letter URIs on nt (strip the
  leading slash urlparse leaves); join Termux example paths with literal
  forward slashes so hints stay POSIX on Windows.
- gateway/status.py + hermes_cli/gateway.py: normalize backslashes to
  forward slashes before the HERMES_HOME substring match so separator
  style cannot defeat profile ownership detection.
- hermes_cli/banner.py: cprint degrades to plain print when
  prompt_toolkit has no console (NoConsoleScreenBufferError on
  redirected/absent Windows stdout).
- hermes_cli/browser_connect.py: posixpath.join for WSL /mnt/c/... bases
  (os.path.join would emit backslashes on nt).
- Test hardening: symlink skip-guards, USERPROFILE alongside HOME for
  ntpath.expanduser, SIGKILL absence skipif fixed via monkeypatch,
  drive-letter URI / separator-normalization / banner-fallback coverage.

Dropped from the original PR: tests/cli/conftest.py fixture and the
AppSession _output monkeypatch — main's merged tests/cli/conftest.py
already handles that prompt_toolkit pollution.

tests/cli/test_cli_image_command.py

@@ -59,6 +59,8 @@ class TestCollectQueryImages:
         home = tmp_path / "home"
         img = _make_image(home / "storage" / "shared" / "Pictures" / "cat.png")
         monkeypatch.setenv("HOME", str(home))
+        # ntpath.expanduser ignores HOME (Python 3.8+) — it wants USERPROFILE.
+        monkeypatch.setenv("USERPROFILE", str(home))
 
         message, images = _collect_query_images("describe this", "~/storage/shared/Pictures/cat.png")