Currently the language service constructs an `AttrAst` anytime it is
missing from a `TemplateAst` path. However, this should only be done
when the path does not contain an "attribute-like" AST, which can
includes bound properties or bound events.
This commit also refactors `visitAttr` to parse bindings only for
microsyntax expressions and does some other minor cleanup to make
linters happy.
This is some cleanup to help the language service eventually use
`BoundDirectivePropertyAst`s for providing completions for template
bindings rather than performing the manual parsing currently done.
PR Close#34743
15b4173a76