[IMP] rma: public tags

Now we can decide which tags are visible for the customer. This way, we
can use them as pseudo-states

TT29594

rma/models/rma_tag.py

@@ -18,6 +18,10 @@ class RmaTag(models.Model):
         translate=True,
         copy=False,
     )
+    is_public = fields.Boolean(
+        string="Public Tag",
+        help="The tag is visible in the portal view",
+    )
     color = fields.Integer(string="Color Index")
     rma_ids = fields.Many2many(comodel_name="rma")