Refactor routing and documentation for SPA deployment

- Updated the application to serve the SPA from the root path instead of /map/, enhancing accessibility.
- Modified redirect logic to ensure backward compatibility with old /map/* URLs.
- Adjusted documentation across multiple files to reflect the new routing structure and API endpoints.
- Improved handling of OAuth redirects and session management in the backend.
- Updated frontend configuration to align with the new base URL settings.

internal/app/oauth.go

@@ -186,7 +186,7 @@ func (a *App) oauthCallback(rw http.ResponseWriter, req *http.Request, provider
 		Secure:   req.TLS != nil,
 		SameSite: http.SameSiteLaxMode,
 	})
-	redirectTo := "/map/profile"
+	redirectTo := "/profile"
 	if st.RedirectURI != "" {
 		if u, err := url.Parse(st.RedirectURI); err == nil && u.Path != "" && !strings.HasPrefix(u.Path, "//") {
 			redirectTo = u.Path