[16.0] web_dark_mode: Dark mode not always set when opening Odoo

[houzefa-abba]

The web_dark_mode module adds a "Dark mode" user setting. With that setting enabled, dark mode activates fine in most cases, but not always:

• ✅ Dark mode is enabled after logout/login (/web/login redirects to /web)
• ✅ Dark mode is enabled when opening a new tab to /web
• ❌ Dark mode is not enabled when opening a new tab to / (/ redirects to /web)

The current workaround is to refresh the page once Odoo is loaded, since by that point it is under /web

Example on runboat:

• http://oca-web-16-0-e5f515797bfc.runboat.odoo-community.org redirects to http://oca-web-16-0-e5f515797bfc.runboat.odoo-community.org/web#action=111&cids=1&menu_id=74 ➔ dark mode not enabled
• Refresh page ➔ dark mode is now enabled