[ADD] mass_mailing_crm: add UTM statistics on mass mailing linked to lead/opportunities

Purpose: better showcase the integration between email marketing and crm
application thanks to UTM links.

Specifications

 * add 2 stat buttons to the mass mailing form;
 * XX Leads -> redirects to lead list view (should include both types: leads
   & opportunities), only visible if Leads are activated in CRM settings;
 * YY Opportunities -> redirects to opportunities list view (only
   opportunities);
 * those stats buttons are linked to UTM trackers used in the mass mailing
   itself: campaign, source and medium. Those can be configured notably using
   the website_link module;
 * display the stat buttons even if no data;
 * update demo data;

This commit is linked to task ID 1872198 and PR #26188.

0 files changed, 0 insertions, 0 deletions