Migrate last 2 packages to TS (10/n)

[thegreatercurve]

Closes #1242! This PR includes:

• Migrated 2 packages:
  • lexical
  • lexical-yjs
• Remove all Flow build configuration
• Remove and rename shared-ts folder to just shared.

I've had to add some any types in the Lexical YJS packages as the types are slightly unclear.

Migration steps

I ran the below script to update the directories automatically, and then fixed each compiler linter error manually:

#!/usr/bin/env bash
DIRECTORIES=(
    "lexical"
    "lexical-yjs"
)

for directory in ${DIRECTORIES[@]}; do
    # Preserve commit history
    for i in $(find ./packages/$directory -iname "*.js" -not -path "*dist*");
        do git mv "$i" "$(echo $i | rev | cut -d '.' -f 2- | rev).ts";
    done
    for i in $(find ./packages/$directory -iname "*.jsx" -not -path "*dist*");
        do git mv "$i" "$(echo $i | rev | cut -d '.' -f 2- | rev).tsx";
    done

    for i in $(find ./packages/$directory -iname "*.ts" -not -path "*dist*" -not -path "flow");
        do sed -i "" "s/boolean %checks/node is ManuallyFindAndReplace/g" $i && sed -i "" "s/: LexicalNode>/ = LexicalNode>/g" $i;
    done
    for i in $(find ./packages/$directory -iname "*.tsx" -not -path "*dist*" -not -path "flow");
        do sed -i "" "s/boolean %checks/node is ManuallyFindAndReplace/g" $i && sed -i "" "s/: LexicalNode>/ = LexicalNode>/g" $i;
    done
    
    npx @khanacademy/flow-to-ts --write "./packages/$directory/**/{!*.d.ts,*.ts}";
    npx @khanacademy/flow-to-ts --write "./packages/$directory/**/*.tsx";
done

npm run prettier:fix;

Bundle sizes

Bundle sizes are consistent with main. Below are some sample packages:

package	main	TS branch
Lexical.prod.js	75K	75K
LexicalYJS.prod.js	17K	17K

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Updated
lexical	✅ Ready (Inspect)	Visit Preview	May 24, 2022 at 8:21AM (UTC)
lexical-playground	✅ Ready (Inspect)	Visit Preview	May 24, 2022 at 8:21AM (UTC)

[yuzhouu]

As all code has been migrated to ts, shouldn't we remove *.d.ts file?

[thegreatercurve]

As all code has been migrated to ts, shouldn't we remove *.d.ts file?

@yuzhouu We should, but I need to make sure that the auto-generated complimentary Flow Types work with our internal codebase.

[zurfyx]

As all code has been migrated to ts, shouldn't we remove *.d.ts file?

@yuzhouu We should, but I need to make sure that the auto-generated complimentary Flow Types work with our internal codebase.

The .d.ts definition also allows us to refine types and visibility (like hiding private properties), no?

[zurfyx]

Great work! 😍