REPL Smart Shift+Enter and Dynamic Smart Cursor

[anthonykim1]

There are two Feature Requests from: #18105 #21838
They are grouped together to provide the smoothest experience: when user wants to press shift+enter and smoothly move between each executable Python code block without having to manually move their cursor.

#19955 (For Execute line/selection and advance to next line, referred to as dynamic smart cursor hereby)
Open Issue: #21778 #21838

Steps in implementing REPL Smart Send (smart shift+enter to the REPL) and dynamic cursor move aka. Move to Next Line (next executable line of code to be more precise):

1. Figure out the workflow of where things start and run when user clicks on run selection/line
2. Send the content of selection & document to the Python Side from Typescript side.
3. Respect and follow previous logic/code for EXPLICIT selection (user has highlighting particular text they want to send to REPL), but otherwise, use newly created smart send code.
4. Receive content of document & selection in Python Side
5. Use AST (From Python standard library) to figure out if selection if selection is part of, for example, dictionary, but look for nodes and how each relates to the top level. If some selection is, for example part of a dictionary, we should run the whole dictionary. Look at how to do this for all top level, so that we run the Minimum Viable Block possible. (For example, if user selects part of a dictionary to run in REPL, it will select and send only the dictionary not the whole class or file, etc)
6. Receive the commands to run in typescript side and send it to the REPL
7. After the user has ran shift+enter(non highlight, meaning there was no explicit highlight of text), thus the incurring of smart send, and we have processed the smart selection, figure out the "next" executable line of code in the currently opened Python file.
8. After figuring out the "next" line number, we will move user's cursor to that line number.

• Additional scope for telemetry EventName.EXECUTION_CODE with the scope of 'line' in addition to differentiate the explicit selection usage compared to line or executable block.
• Drop 3.7 support before merging since end_line attribute of the AST module is only supported for Python version 3.8 and above.
• Python tests for both smart selection, dynamic cursor move.
• TypeScript tests for smart selection, dynamic cursor move.

Notes:

• To be shipped after dropping Python3.7 support, since end_lineno, which is critical in smart shift+enter logic, is only for Python version GREATER than 3.7 Update (9/14/23: Python 3.7 support is dropped from the VS Code Python extension: Drop Python 3.7 support  #21962)
• Code in regards to this feature(s) should be wrapped in standard experiment (not setting based experiment)
• Respective Telemetry should also be attached
• EXPLICIT (highlight) selection of the text, and shift+enter/run selection should respect user's selection and send AS IT IS. (When the user selects/highlight specifically what they want to send, we should respect user's selection and send the selection as they are selected)
• Smart Shift+Enter should be shipped together with dynamic smart cursor movement for smoothest experience.
  This way user could shift+enter line by line (or more accurately top block after another top block) as they shift+enter their code.
• Be careful with line_no usage between vscode and python as vscode counts line number starting from 0 and python ast start as normal (starts from line 1)) So vscode_lineno + 1 = python_ast_lineno