Update Tender Approval Status to Include Submitted State and Revise API Documentation

- Changed the approval status from "approved" to "submitted" in various locations, including entity definitions, forms, and service methods, to accurately reflect the tender approval process.
- Updated API documentation in Swagger JSON, YAML, and Go files to describe the new status options ("submitted" and "rejected") and their corresponding descriptions.
- Enhanced the tender approval statistics structures to include a count for submitted tenders, improving the overall data model for tender management.
- These changes ensure clarity in the tender approval workflow and enhance the usability of the API for clients interacting with tender approvals.

internal/tender_approval/validation.go

@@ -48,7 +48,7 @@ func IsValidSubmissionMode(mode string) bool {
 // IsValidStatus validates if the approval status is valid
 func IsValidStatus(status string) bool {
 	validStatuses := []string{
-		string(ApprovalStatusApproved),
+		string(ApprovalStatusSubmitted),
 		string(ApprovalStatusRejected),
 	}