[TASK]: Save as semantic for Stratify operation

[mwdchang]

See https://www.figma.com/design/uXs52uABr8tliYK5UltgaB/Terarium---August-2024?node-id=296-86122&t=tXroImdXsfn57gWe-0

There are several parts for this change:

• If not already, we want to generate semi-sensible names for the models created from stratify operation from the input stratification criteria. e.g. "stratified SIR with 4 distinct age groups"
• Add a save for reuse button, that, when invoked, will add the output asset into the ProjectAsset proper
• Don't worry too much about the renaming feature for now (e.g. change the output model's name), we will revisit this. (See: [TASK]: Save semantics - Devise an asset rename propagation scheme #4557)