This commit replaces getters in `ComposerSuggestion` component to fields in
model `ComposerSuggestion`.
Getters in component are a problem for many reasons, notably that business
code is in component and not in modelling. Code that are not in modelling are
hacky, hard to maintain, and very prone to bug. That's why it's important to
move most code in components to models.
Task-2793280
closesodoo/odoo#88315
Signed-off-by: Alexandre Kühn (aku) <aku@odoo.com>