Currently, when a new survey is created, the three notification fields below inherit their
values from the parent survey group (or from the global defaults). There is no built-in way
to define what those defaults should be, nor to auto-fill the bounce address from the survey
owner's email.

We would like to be able to set, per instance (or per survey group), the following defaults
applied automatically to every newly created survey:

1. "Administrator" (admin) -> Inherit: OFF, field left empty
2. "Administrator email" (adminemail) -> Inherit: OFF, field left empty
3. "Bounce email" (bounce_email) -> auto-filled with the survey owner's email address
   (Inherit: OFF)

Motivation / Use case

We manage many surveys, each owned by a different person. We want bounce/delivery-error
notifications to go directly to the survey owner, without having to manually edit the
"Notification & data management" tab of every single survey after creation. Today this is a
repetitive, error-prone manual step: if an administrator forgets to switch "Inherit" off and
to set the correct bounce address, error notifications silently go to the wrong recipient (or
to the global admin), which can mean lost feedback and undetected invalid addresses.

Desired behaviour

At survey creation (UI and RemoteControl2 API), the three fields above should be initialized
from a configurable default policy rather than blindly inheriting:

• a global / per-group setting defining the default state of inheritan, inheritema,
  inheritbnc and the default content of admin / adminemail / bounce_email;
• a special token/placeholder (e.g. {owner_email}) usable as the default for bounce_email,
  resolved to the email of the user who owns the survey (users.email of owner_id).

Proposed implementation (suggestions, not prescriptive)

• Add new global settings in the "Global survey settings" panel for the three fields.
• When a survey is created, apply these defaults instead of pure group inheritance.
• Support a {owner_email} placeholder for bounce_email, resolved at save time from the
  owner's account.