Adds tfe_workspace_settings resource

This resource is added for two reasons: to break the circular dependency between tfe_workspace agent_pool_id and tfe_agent_pool_allowed_workspaces, as well as create a resource symmetry between tfe_organization_default_execution_mode (will be renamed to tfe_organization_default_settings in a followup commit)

Author: brandonc

internal/provider/provider_next.go

@@ -5,7 +5,9 @@ package provider
 
 import (
 	"context"
+	"fmt"
 	"os"
+	"regexp"
 
 	"github.com/hashicorp/terraform-plugin-framework/datasource"
 	"github.com/hashicorp/terraform-plugin-framework/provider"
@@ -23,6 +25,14 @@ type frameworkProvider struct{}
 // Compile-time interface check
 var _ provider.Provider = &frameworkProvider{}
 
+// Can be used to construct ID regexp patterns
+var base58Alphabet = "[1-9A-HJ-NP-Za-km-z]"
+
+// IDPattern constructs a regexp pattern for Terraform Cloud with the given prefix
+func IDPattern(prefix string) *regexp.Regexp {
+	return regexp.MustCompile(fmt.Sprintf("^%s-%s{16}$", prefix, base58Alphabet))
+}
+
 // FrameworkProviderConfig is a helper type for extracting the provider
 // configuration from the provider block.
 type FrameworkProviderConfig struct {
@@ -121,5 +131,6 @@ func (p *frameworkProvider) Resources(ctx context.Context) []func() resource.Res
 	return []func() resource.Resource{
 		NewResourceVariable,
 		NewSAMLSettingsResource,
+		NewResourceWorkspaceSettings,
 	}
 }