refactor: shorten model and table prefixes

backend/internal/models/project_event.go

@@ -2,7 +2,7 @@ package models
 
 import "time"
 
-type SenlinAgentProjectEvent struct {
+type SaProjectEvent struct {
 	ID              uint   `gorm:"primaryKey"`
 	Identity        string `gorm:"type:char(36);uniqueIndex"`
 	ProjectID       uint   `gorm:"index;not null"`
@@ -17,6 +17,6 @@ type SenlinAgentProjectEvent struct {
 	CreatedAt       time.Time
 }
 
-func (SenlinAgentProjectEvent) TableName() string {
-	return "senlin_agent_project_events"
+func (SaProjectEvent) TableName() string {
+	return "sa_project_events"
 }