fix: template name replacement in package.json

[Esemesek]

Summary:

Fixes #1456

Seems like our special treatment of package.json during init caused not everything to be replaced correctly. With this fix everything will be replaced correctly except the name won't be converted to lowercase npmjs package naming.

Test Plan:

Added test case assertions for this one in the editTemplate.test.ts.

[Esemesek]

@thymikee @grabbou What do you think about parsing package.json additionally to convert the name keyword to be lowercased?

[thymikee]

I'm good with this change. @grabbou WDYT? I wouldn't bother about the package name in package.json, because we don't init libraries.