Make getTextOfIdentifierOrLiteral only accept Identifier | StringLiteralLike | NumericLiteral

[ghost]

Like with #21981, tightening this function required reexamining some casts elsewhere.

[weswigham]

This is stealth mode also enabling string literal completions within no substitution template literals, no? That should probably be tested so we know if we break it. Otherwise, seems fine.

[ghost]

In completions.ts, we are getting the name from getNameOfDeclaration(m);. That shouldn't ever be a NoSubstitutionTemplateLiteral (even given the changes to getDeclarationName, since getNameOfDeclaration still won't return one).
Also, we already support string literal completions inside NoSubstitutionTemplateLiteral -- see completionListAfterSTringLiteralTypeWithNoSubstitutionTemplateLiteral.ts.