VoIP now uses shared translation helper logic from the broader web platform instead of keeping its own copy. This reduces duplication and helps keep phone-related interface text consistent and easier to maintain across Odoo.

Community counterpart: https://github.com/odoo/odoo/pull/211279

WhatsApp tests were updated to match a platform change in how messages are categorized. This helps keep WhatsApp-related behavior aligned with the main messaging system and reduces risk of future inconsistencies.

The community counterpart of this commit replaces "is_note", "is_discussion" and "subtype_description" fake message fields by "subtype_id" which exists on message. This commit adapts whatsapp tests after this change.

task-4676083

community: https://github.com/odoo/odoo/pull/209487