Configurable conflict solutions to automate massive cases

Is your feature request related to a problem? Please describe.
Sometimes tens, hundreds or thousands of files are conflicting from Nextcloud client POV

Describe the solution you'd like
Both server and client should support a policy to solve automatically each case. Server can notify recommended action to client, and client can apply its mandatory behaviour. Server configuration should allow differentiate between clients.

• Server side policy to recommend each client per each case: a) Ask user (default) b) Client downloads server's content c) Client uploads client's content.
• Client side policy to apply per each case: a) Ask user b) Client downloads server's content c) Client uploads client's content. d) Apply server's policy (default).

Describe alternatives you've considered

• Allow user of desktop client to select massively conflicts and trigger action: a) Upload b) Download c) Defer d) Ignore

Additional context
A sysop must have a way to implement Nextcloud infrastructure with unexperienced users, to synchronizations be unattended with conflicts resolutions unattended.

The issue mentions server and client conflict policies but names no files, tests, or entry points. Start by mapping how conflict handling and client synchronization are represented in this repository and identify the client-side project separately. Done would require an agreed design and coordinated server/client implementation for policy-based conflict resolution.