fix: correct GetProperty bug, init to use .ax/, add default aliases, split e2e tests, add due date tests

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/models/node.go

@@ -1,15 +1,48 @@
 package models
 
 import (
+	"encoding/json"
+	"fmt"
 	"slices"
 	"strings"
+	"time"
 )
 
+// Date is a date-only time value that marshals as "YYYY-MM-DD" in JSON.
+type Date struct{ time.Time }
+
+// ParseDate parses a date string in "YYYY-MM-DD" or RFC3339 format.
+func ParseDate(s string) (Date, error) {
+	for _, layout := range []string{"2006-01-02", time.RFC3339} {
+		if t, err := time.Parse(layout, s); err == nil {
+			return Date{t.UTC()}, nil
+		}
+	}
+	return Date{}, fmt.Errorf("cannot parse date %q: expected YYYY-MM-DD", s)
+}
+
+func (d Date) MarshalJSON() ([]byte, error) {
+	return json.Marshal(d.Format("2006-01-02"))
+}
+
+func (d *Date) UnmarshalJSON(b []byte) error {
+	var s string
+	if err := json.Unmarshal(b, &s); err != nil {
+		return err
+	}
+	parsed, err := ParseDate(s)
+	if err != nil {
+		return err
+	}
+	*d = parsed
+	return nil
+}
+
 type Node struct {
 	ID        string              `json:"id"`
 	Title     string              `json:"title"`
 	Content   string              `json:"content,omitempty"`
-	DueDate   string              `json:"due_date,omitempty"`
+	DueDate   *Date               `json:"due_date,omitempty"`
 	CreatedAt string              `json:"created_at"`
 	UpdatedAt string              `json:"updated_at"`
 	Tags      []string            `json:"tags,omitempty"`
@@ -85,7 +118,9 @@ func (n *Node) RemoveRelation(relType RelType, target string) {
 func (n *Node) GetProperty(k string) string {
 	prefix := "_" + k + "::"
 	for _, t := range n.Tags {
-		return strings.TrimPrefix(t, prefix)
+		if strings.HasPrefix(t, prefix) {
+			return strings.TrimPrefix(t, prefix)
+		}
 	}
 	return ""
 }