Migrate legacy Wiki desktop icon route to /wiki-app

[Copilot]

Some installed sites still have the Wiki Desktop Icon pointing to the old /wiki route, which now breaks navigation after the app route rename. This change ensures existing installations are corrected during migration.

• Migration patch

  • Adds wiki.wiki.doctype.wiki_settings.patches.update_wiki_desktop_icon_link.
  • Updates Desktop Icon Wiki link to /wiki-app only when the stored value is legacy (/wiki, wiki, /wiki/).
  • No-op when the icon is missing or already correct.

• Patch wiring

  • Registers the patch in wiki/patches.txt so it is applied in normal migrate flow.

• Regression coverage

  • Extends wiki/wiki/doctype/wiki_settings/test_wiki_settings.py with a focused test validating legacy link migration behavior.

def execute():
	if not frappe.db.exists("Desktop Icon", "Wiki"):
		return

	current_link = frappe.db.get_value("Desktop Icon", "Wiki", "link")
	if current_link in {"/wiki", "wiki", "/wiki/"}:
		frappe.db.set_value("Desktop Icon", "Wiki", "link", "/wiki-app", update_modified=False)

• Fixes Desktop Icon link update to wiki-app #732