Use content tag

[NullVoxPopuli]

Resolves: https://github.com/typed-ember/glint/issues/609 Blocked by: https://github.com/embroider-build/content-tag/issues/19 Blocked by: https://github.com/embroider-build/content-tag/pull/31

Unblocks: https://github.com/NullVoxPopuli/polaris-starter/pull/11

Problem:

• content-tag requires syntax to be correct
• LSPs need fault-tolerant parsing to aid in intellisense, suggestions and all that

This isn't a new problem for Glint, but it does take things in the wrong direction a bit.

[NullVoxPopuli]

Observations:

Deleting the closing </template>

Example 1

kinda goofy

Before this PR, the experience is worse

Example 2

this actually makes sense and provides meaningful feedback about the missing closing </template>, which I believe is an improvement?

Before this PR, the experience is worse

Deleting the opening <template>

Example 1

sqigglies everywhere. maybe this is something we can get our swc parser to help with though?

Before this PR, the experience is not helpful, but :shrug: when it comes to deciding if better or worse, imo

Deliberate syntax error

"importing a number"

Before this PR, the experience is better

extra quote

Before this PR, the experience is better

number * string

Before this PR, the experience is better

forgetting to give a variable a value

Before this PR, the experience is better

fun thing(s)

### accidentally discovered function noop shorthand this is actually valid, but looks goofy 

[NullVoxPopuli]

I broke something here, so I'm starting over here: https://github.com/typed-ember/glint/pull/655