[Feature] Add support to save LLM Playground runs

[YourTechBud]

Problem faced:

• Sometimes we use the LLM playground for several critical things like:
  • Making a quick PoC to confirm if something is doable or not
  • Writing light weigh test cases
  • Building mini demos
• It's painful to keep recreating them

Proposed solution:

• Allow us to store Playground sessions for later use
• Each session should have a name (Could be autogenerated)
• Allow organizing sessions into directories