[Prototype] Experiment with pruning provider schemas

[cam72cam]

We load the full provider schemas into OpenTofu, regardless of what small subsection we actually use. I'm experimenting with filtering out resources that are not used by the configuration or state.

The current machinery around provider initialization and schemas is ... janky. This prototype digs into that jank to show the promise of the idea.

Contrived Example:

terraform {
        required_providers {
                aws = { source = "hashicorp/aws" }
                awscc = { source = "hashicorp/awscc" }
                azurerm = { source = "hashicorp/azurerm" }
                google = { source = "hashicorp/google" }
                google-beta = { source = "hashicorp/google-beta" }
        }
}

resource "local_file" "myfile" {
  content  = "stuff"
  filename = "myfile"
}

output "foo" {
        value = "bar"
}

https://gist.github.com/cam72cam/aa55271ebe2bbafc9586d1673a007581

• A full 2 seconds faster
• 148MB peak down to 46MB peak
• Schema memory usage down from ~70MB to ~1MB

This also reduces the risk of #2730

Target Release

1.11.0

Checklist

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[github-actions]

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