r/aws_bedrockagent_agent: use configured prepare_agent value

This changes removes logic in the read operation which adjusted the `prepare_agent` argument based on whether or not the agent status was `Prepared`. Now the configured `prepare_agent` value is always used, regardless of the status of the agent. If omitted, the default value of `true` is inherited, meaning that by default agents will always be prepared as part of the create or update operation. The `prepare_agent` value is now also set to `true` when an agent is imported.

```console
% make testacc PKG=bedrockagent TESTS=TestAccBedrockAgentAgent_
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go1.22.2 test ./internal/service/bedrockagent/... -v -count 1 -parallel 20 -run='TestAccBedrockAgentAgent_'  -timeout 360m

--- PASS: TestAccBedrockAgentAgent_basic (19.66s)
--- PASS: TestAccBedrockAgentAgent_full (19.67s)
--- PASS: TestAccBedrockAgentAgent_tags (35.51s)
--- PASS: TestAccBedrockAgentAgent_update (37.46s)
PASS
ok      github.com/hashicorp/terraform-provider-aws/internal/service/bedrockagent       42.493s
```

.changelog/37405.txt

@@ -0,0 +1,3 @@
+```release-note:bug
+resource/aws_bedrockagent_agent: Fix to use the configured `prepare_agent` value (or default value of `true` when omitted) for all create and update operations
+```

internal/service/bedrockagent/agent.go

@@ -17,6 +17,7 @@ import (
 	"github.com/hashicorp/terraform-plugin-framework-validators/int64validator"
 	"github.com/hashicorp/terraform-plugin-framework-validators/listvalidator"
 	"github.com/hashicorp/terraform-plugin-framework-validators/stringvalidator"
+	"github.com/hashicorp/terraform-plugin-framework/path"
 	"github.com/hashicorp/terraform-plugin-framework/resource"
 	"github.com/hashicorp/terraform-plugin-framework/resource/schema"
 	"github.com/hashicorp/terraform-plugin-framework/resource/schema/booldefault"
@@ -55,7 +56,6 @@ func newAgentResource(context.Context) (resource.ResourceWithConfigure, error) {
 
 type agentResource struct {
 	framework.ResourceWithConfigure
-	framework.WithImportByID
 	framework.WithTimeouts
 }
 
@@ -249,8 +249,6 @@ func (r *agentResource) Read(ctx context.Context, request resource.ReadRequest,
 		return
 	}
 
-	data.PrepareAgent = types.BoolValue(agent.AgentStatus == awstypes.AgentStatusPrepared)
-
 	response.Diagnostics.Append(response.State.Set(ctx, &data)...)
 }
 
@@ -366,6 +364,12 @@ func (r *agentResource) Delete(ctx context.Context, request resource.DeleteReque
 	}
 }
 
+func (r *agentResource) ImportState(ctx context.Context, req resource.ImportStateRequest, resp *resource.ImportStateResponse) {
+	resp.Diagnostics.Append(resp.State.SetAttribute(ctx, path.Root(names.AttrID), req.ID)...)
+	// Set prepare_agent to default value on import
+	resp.Diagnostics.Append(resp.State.SetAttribute(ctx, path.Root("prepare_agent"), true)...)
+}
+
 func (r *agentResource) ModifyPlan(ctx context.Context, request resource.ModifyPlanRequest, response *resource.ModifyPlanResponse) {
 	r.SetTagsAll(ctx, request, response)
 }

internal/service/bedrockagent/agent_test.go

@@ -38,6 +38,7 @@ func TestAccBedrockAgentAgent_basic(t *testing.T) {
 					resource.TestCheckResourceAttr(resourceName, "agent_name", rName),
 					resource.TestCheckResourceAttr(resourceName, "prompt_override_configuration.#", "1"),
 					resource.TestCheckResourceAttr(resourceName, names.AttrDescription, "basic claude"),
+					resource.TestCheckResourceAttr(resourceName, "prepare_agent", "true"),
 				),
 			},
 			{