Merge pull request #31874 from hashicorp/backport/jbardin/remove-planned-during-import/genuinely-shining-boar

Backport of RemovePlannedResourceInstanceObjects during import into v1.3

Backport of prune unused nodes from a destroy plan graph into v1.3

Merge pull request #31872 from hashicorp/backport/jbardin/destroy-edge-cycles/instantly-prepared-hagfish

Backport of prevent cycles when connecting destroy nodes into v1.3

Backport of Update workspace documentation into v1.3

Merge pull request #31855 from hashicorp/backport/alisdair/pre-convert-optional-defaults/virtually-able-mouse

Backport of Upgrade hcl to fix crash with optional attributes into v1.3

Backport of fixed typo: `startsswith` -> `startswith` into v1.3

Merge pull request #31832 from hashicorp/backport/optional-type-attributes-note/inherently-dear-goat

Backport of Remove unnecessary version note into v1.3

Backport of Add internals overview page to navigation into v1.3

Backport of Update taint.mdx into v1.3

We've removed the main documentation pages for the backends that are
removed in Terraform v1.3, but we'll leave a small callout note so that
the backend names are still reachable through our search index once the
v1.3 docs are the active version.

The primary goal here is to help folks who have inherited configurations
using older versions of Terraform to learn about features they see in those
configurations, so the main thing here is the link to the older release
docs which include those. However, this is also a good opportunity to link
to the upgrade guide content which describes some possible migration
paths away from these removed backends.

Merge pull request #31805 from hashicorp/backport/alisdair/skip-defaults-apply-for-null/evenly-vast-tahr

Backport of Do not apply type defaults to null values into v1.3

Co-authored-by: Matthew Garrell <69917312+mgarrell777@users.noreply.github.com>
Co-authored-by: Laura Pacilio <83350965+laurapacilio@users.noreply.github.com>
Co-authored-by: Kevin Wang <kwangsan@gmail.com>
Co-authored-by: Judith Malnick <judith@hashicorp.com>
Co-authored-by: Martin Atkins <mart@degeneration.co.uk>
Co-authored-by: HashiBot <62622282+hashibot-web@users.noreply.github.com>
Co-authored-by: temp <temp@hashicorp.com>
Co-authored-by: Bryce Kalow <bkalow@hashicorp.com>

Backport of Remove legacy provisioners from docs into v1.3