Query pipeline architecture issues

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This issue tracks longer-term, architectural changes to the query pipeline.

In progress/done in 8.0

• Pruning improvements:
  • Prune all SelectExpressions, not just those in Tables #31083
  • Prune OPENJSON columns list #32668
  • Track prunability of inner joins on the expression itself  #32674
  • Move all pruning code to the pruner and make it an immutable visitor  #32817
• Table alias work:
  • Clean table alias generation and generate unique aliases up-front #32784. Required to move from TableReferenceExpression to simple by-alias referencing, since aliases need to be generated before tables are instantiated and not change (barring a post-processing pass).
  • Make TableExpressionBase.Alias immutable  #32815
• Redo query column/table relationship without TableReferenceExpression  #32812
• Extract SelectExpression construction out to RelationalQueryableMethodTranslatingEV #32877
• Make our SQL tree fully immutable #32927

Backlog

• Stop referencing the query from ProjectionBindingExpression in the shaper #32980
• Use inheritance instead of annotations for TableExpressionBase (specifically temporal tables) #33044
• Query: Re-evaluate concept of pending selector in nav expansion #20291
  • Query: remove nav expansion as a way to tackle the pending selector problem  #32957
• Consider having a relational expression representing OPENJSON, json_each and so on #32576
• Stop producing duplicate subqueries in SQL #32277
• Allow standalone set operations (and ValuesExpression) without a wrapping SelectExpression #32890
• Consider doing property/navigation binding entirely from RelationalSqlTranslatingExpressionVisitor #31309
• Consider introducing nullability on SqlExpression #33889
• DRY around getting the projection from ShapedQueryExpression #31015
• Consider breaking out SelectExpression internal logic to the translation visitors #31049
• Query: convert identifiers to be generic SqlExpressions rather than ColumnExpressions #31326
• Query: Pay your (technical) debt on time #18923