feat(dep_ensure): complete Windows bootstrap — dep_ensure + install.ps1 + detection (#27845)

* feat(dep_ensure): complete Windows bootstrap — dep_ensure + install.ps1 + detection

dep_ensure.py gains Windows awareness: PowerShell invocation, platform-
specific browser detection, (path, shell) tuple returns.

install.ps1 gains -Ensure/-PostInstall modes using npm -g --prefix
(aligned with install.sh) and agent-browser install for Chromium.

browser_tool.py gains node/ in candidate dirs for Windows .cmd shims.
Both install scripts bundled in pip wheel.

Tracking: #27826

* fix(install.ps1): add --ignore-scripts to npm install for camofox

@askjo/camofox-browser has a dependency (impit) whose postinstall
script runs `npx only-allow pnpm`, which fails under npm. Adding
--ignore-scripts avoids the spurious failure without affecting
functionality.

Tracking: #27826

* fix: remove duplicate install scripts from git

CI already copies scripts/install.{sh,ps1} into hermes_cli/scripts/
during wheel build. No need to commit copies — .gitignore keeps them
out, _find_install_script() falls back to scripts/ for git-clone users.

Tracking: #27826

* fix: address review — remove env_extra, fix ps1 error handling

- Remove unused env_extra parameter from ensure_dependency()
- Invoke-EnsureMode node case now uses Test-Node consistently
- Install-AgentBrowser uses throw instead of exit 1

.github/workflows/upload_to_pypi.yml

@@ -71,10 +71,11 @@ jobs:
           test -f hermes_cli/web_dist/index.html || { echo "ERROR: web_dist not built"; exit 1; }
           test -f hermes_cli/tui_dist/entry.js || { echo "ERROR: tui_dist not built"; exit 1; }
 
-      - name: Bundle install.sh into wheel
+      - name: Bundle install scripts into wheel
         run: |
           mkdir -p hermes_cli/scripts
           cp scripts/install.sh hermes_cli/scripts/install.sh
+          cp scripts/install.ps1 hermes_cli/scripts/install.ps1
 
       - name: Build wheel and sdist
         run: uv build --sdist --wheel