Logging and error handling improvements, bug fixes (#21)

- Uniformed logs and diagnostics:
  - Logging and adding to diagnostics is done by the highest level function (Create/Read/Update/Delete/Import) using `LogAndAddError`
  - Lower-level routines' signature changed to return error instead of writing to diagnostics
  - Standardize summary and details across services
  - Removed manual adding of relevant variables to details (they're in the context, TF adds them to logs)
- Changed validators to be closer to official implementation
- Fix logging wrong output after wait
- Fix Argus checking wrong diagnostics
- Fix Resource Manager not updating state after project update
- Fix unnecessary pointer in LogAndAddError

stackit/services/postgresflex/user/datasource.go

@@ -45,7 +45,7 @@ func (r *userDataSource) Configure(ctx context.Context, req datasource.Configure
 
 	providerData, ok := req.ProviderData.(core.ProviderData)
 	if !ok {
-		resp.Diagnostics.AddError("Unexpected Data Source Configure Type", fmt.Sprintf("Expected stackit.ProviderData, got %T", req.ProviderData))
+		core.LogAndAddError(ctx, &resp.Diagnostics, "Error configuring API client", fmt.Sprintf("Expected configure type stackit.ProviderData, got %T", req.ProviderData))
 		return
 	}
 
@@ -64,12 +64,12 @@ func (r *userDataSource) Configure(ctx context.Context, req datasource.Configure
 	}
 
 	if err != nil {
-		resp.Diagnostics.AddError("Could not Configure API Client", err.Error())
+		core.LogAndAddError(ctx, &resp.Diagnostics, "Error configuring API client", fmt.Sprintf("Configuring client: %v", err))
 		return
 	}
 
-	tflog.Info(ctx, "Postgresflex user client configured")
 	r.client = apiClient
+	tflog.Info(ctx, "PostgresFlex user client configured")
 }
 
 // Schema defines the schema for the resource.
@@ -150,19 +150,22 @@ func (r *userDataSource) Read(ctx context.Context, req datasource.ReadRequest, r
 
 	recordSetResp, err := r.client.GetUser(ctx, projectId, instanceId, userId).Execute()
 	if err != nil {
-		core.LogAndAddError(ctx, &resp.Diagnostics, "Error reading user", err.Error())
+		core.LogAndAddError(ctx, &resp.Diagnostics, "Error reading user", fmt.Sprintf("Calling API: %v", err))
 		return
 	}
 
-	// Map response body to schema and populate Computed attribute values
+	// Map response body to schema
 	err = mapFields(recordSetResp, &model)
 	if err != nil {
-		core.LogAndAddError(ctx, &resp.Diagnostics, "Error mapping fields", err.Error())
+		core.LogAndAddError(ctx, &resp.Diagnostics, "Error reading user", fmt.Sprintf("Processing API payload: %v", err))
 		return
 	}
 
 	// Set refreshed state
 	diags = resp.State.Set(ctx, model)
 	resp.Diagnostics.Append(diags...)
-	tflog.Info(ctx, "Postgresql user read")
+	if resp.Diagnostics.HasError() {
+		return
+	}
+	tflog.Info(ctx, "PostgresFlex user read")
 }