feat(merge): 🎉 Add support for merging constraints and indexes

* Implement mergeConstraints to handle table constraints
* Implement mergeIndexes to handle table indexes
* Update mergeTables to include constraints and indexes during merge

pkg/merge/merge.go

@@ -120,8 +120,10 @@ func (r *MergeResult) mergeTables(schema *models.Schema, source *models.Schema,
 		}
 
 		if tgtTable, exists := existingTables[tableName]; exists {
-			// Table exists, merge its columns
+			// Table exists, merge its columns, constraints, and indexes
 			r.mergeColumns(tgtTable, srcTable)
+			r.mergeConstraints(tgtTable, srcTable)
+			r.mergeIndexes(tgtTable, srcTable)
 		} else {
 			// Table doesn't exist, add it
 			newTable := cloneTable(srcTable)
@@ -151,6 +153,50 @@ func (r *MergeResult) mergeColumns(table *models.Table, srcTable *models.Table)
 	}
 }
 
+func (r *MergeResult) mergeConstraints(table *models.Table, srcTable *models.Table) {
+	// Initialize constraints map if nil
+	if table.Constraints == nil {
+		table.Constraints = make(map[string]*models.Constraint)
+	}
+
+	// Create map of existing constraints
+	existingConstraints := make(map[string]*models.Constraint)
+	for constName := range table.Constraints {
+		existingConstraints[constName] = table.Constraints[constName]
+	}
+
+	// Merge constraints
+	for constName, srcConst := range srcTable.Constraints {
+		if _, exists := existingConstraints[constName]; !exists {
+			// Constraint doesn't exist, add it
+			newConst := cloneConstraint(srcConst)
+			table.Constraints[constName] = newConst
+		}
+	}
+}
+
+func (r *MergeResult) mergeIndexes(table *models.Table, srcTable *models.Table) {
+	// Initialize indexes map if nil
+	if table.Indexes == nil {
+		table.Indexes = make(map[string]*models.Index)
+	}
+
+	// Create map of existing indexes
+	existingIndexes := make(map[string]*models.Index)
+	for idxName := range table.Indexes {
+		existingIndexes[idxName] = table.Indexes[idxName]
+	}
+
+	// Merge indexes
+	for idxName, srcIdx := range srcTable.Indexes {
+		if _, exists := existingIndexes[idxName]; !exists {
+			// Index doesn't exist, add it
+			newIdx := cloneIndex(srcIdx)
+			table.Indexes[idxName] = newIdx
+		}
+	}
+}
+
 func (r *MergeResult) mergeViews(schema *models.Schema, source *models.Schema) {
 	// Create map of existing views
 	existingViews := make(map[string]*models.View)