Expressions (Interpreter) 👉 New Platform

[streamich]

A step-by-step complete plan to move Expressions/Interpreter to the New Platform.

• Finish Expressions service shim (expression service #42337 + follow up)

Must have:

• Extract server-side initialization out of Interpreter
• TypeScriptify and Jestify (1 week)
• Move Expressions executor core_plugins/interpreter 👉 core_plugins/expressions
• Move simple Expressions functions core_plugins/interpreter 👉 core_plugins/expressions
• Move complex Expressions functions core_plugins/interpreter 👉 ?
• Move Expressions NP-ready plugin core_plugins/expressions 👉src/plugins/expressions
• Move visualization renderer 👉visualizations plugin

Should have:

• Move server-side core_plugins/interpreter code to Canvas

Parent issues: #31968, #46909

[elasticmachine]

Pinging @elastic/kibana-app-arch