Some inline declarations are of the form:
```
exports.<name> = <implementation>;
```
In this case the declaration `node` is `exports.<name>`.
When interpreting such inline declarations we actually want
to visit the `implementation` expression rather than visiting
the declaration `node`.
This commit adds `implementation?: ts.Expression` to the
`InlineDeclaration` type and updates the interpreter to visit
these expressions as described above.
PR Close#39267
ac0016cd82