feat: add user secrets SDK types and db2sdk converters (#24102)

Adds the SDK types and database-to-SDK conversion helpers for the user secrets feature.

codersdk/usersecrets.go

@@ -0,0 +1,41 @@
+package codersdk
+
+import (
+	"time"
+
+	"github.com/google/uuid"
+)
+
+// UserSecret represents a user secret's metadata. The secret value
+// is never included in API responses.
+type UserSecret struct {
+	ID          uuid.UUID `json:"id" format:"uuid"`
+	Name        string    `json:"name"`
+	Description string    `json:"description"`
+	EnvName     string    `json:"env_name"`
+	FilePath    string    `json:"file_path"`
+	CreatedAt   time.Time `json:"created_at" format:"date-time"`
+	UpdatedAt   time.Time `json:"updated_at" format:"date-time"`
+}
+
+// CreateUserSecretRequest is the payload for creating a new user
+// secret. Name and Value are required. All other fields are optional
+// and default to empty string.
+type CreateUserSecretRequest struct {
+	Name        string `json:"name"`
+	Value       string `json:"value"`
+	Description string `json:"description,omitempty"`
+	EnvName     string `json:"env_name,omitempty"`
+	FilePath    string `json:"file_path,omitempty"`
+}
+
+// UpdateUserSecretRequest is the payload for partially updating a
+// user secret. At least one field must be non-nil. Pointer fields
+// distinguish "not sent" (nil) from "set to empty string" (pointer
+// to empty string).
+type UpdateUserSecretRequest struct {
+	Value       *string `json:"value,omitempty"`
+	Description *string `json:"description,omitempty"`
+	EnvName     *string `json:"env_name,omitempty"`
+	FilePath    *string `json:"file_path,omitempty"`
+}