rename: Note→Post/Line (dashboard); Recognition→Note (drama); new-post/my-posts to billboard

- dashboard: Note→Post, Item→Line across models, forms, views, API, urls & tests
- new-post (9×3) & my-posts (3×3) applets migrate from dashboard→billboard context; billboard view passes form & recent_posts
- drama: Recognition→Note, related_name notes; billboard URL /recognition/→/my-notes/, set-palette at /note/<slug>/set-palette
- recognition.js→note.js (module Note, data.note key); recognition-page.js→note-page.js; .recog-*→.note-*
- _recognition.scss→_note.scss; BillNotes page header; applet slug billboard-recognition→billboard-notes (My Notes)
- NoteSpec.js replaces RecognitionSpec.js; test_recognition.py→test_applet_my_notes.py
- 4 migrations applied: dashboard 0004, applets 0011+0012, drama 0005; 683 ITs green

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

src/apps/api/serializers.py

@@ -1,30 +1,30 @@
 from rest_framework import serializers
 
-from apps.dashboard.models import Item, Note
+from apps.dashboard.models import Line, Post
 from apps.lyric.models import User
 
 
-class ItemSerializer(serializers.ModelSerializer):
+class LineSerializer(serializers.ModelSerializer):
     text = serializers.CharField()
 
     def validate_text(self, value):
-        note = self.context["note"]
-        if note.item_set.filter(text=value).exists():
+        post = self.context["post"]
+        if post.lines.filter(text=value).exists():
             raise serializers.ValidationError("duplicate")
         return value
 
     class Meta:
-        model = Item
+        model = Line
         fields = ["id", "text"]
 
-class NoteSerializer(serializers.ModelSerializer):
+class PostSerializer(serializers.ModelSerializer):
     name = serializers.ReadOnlyField()
     url = serializers.CharField(source="get_absolute_url", read_only=True)
-    items = ItemSerializer(many=True, read_only=True, source="item_set")
+    lines = LineSerializer(many=True, read_only=True)
 
     class Meta:
-        model = Note
-        fields = ["id", "name", "url", "items"]
+        model = Post
+        fields = ["id", "name", "url", "lines"]
 
 class UserSerializer(serializers.ModelSerializer):
     class Meta: