Improve unresolved variable messaging when appearing in the context of a builtin.

[RCHowell]

Requested Solution/Feature

Today, we do not immediately propagate an unresolved variable error when performing function resolution. Instead we pass the error node as a MISSING expression into function resolution. The result is that the error message is confusing. It appears like we weren't able to resolve a function, but really we weren't able to resolve a function because we couldn't resolve on of its arguments.

For example,

T : << { a: int } >>

SELECT upper(b) FROM T

-- !! ERROR Unknown function `upper(<missing>)`

When really what has happened is we could not resolve T.b as the struct only has a field T.a. The expression upper(MISSING) is sent to the function resolver which kicks this back saying that's not a valid function. But it's only not valid because we couldn't resolve b.

Describe Alternatives

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Additional Context

We should check errors here, https://github.com/partiql/partiql-lang-kotlin/blob/main/partiql-planner/src/main/kotlin/org/partiql/planner/internal/typer/PlanTyper.kt#L585

DoD (Definition of Done)

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