brief sprint C3.a: Note unlock spawns Line + Brief on the user's per-category Post; banner JS consumes the new brief payload (FYI → post detail, square → my-notes) — TDD

Wires the C2 Brief model into the existing Note-unlock pipeline. Per the per-category Post model: each user has a single Post(owner=user, kind=NOTE_UNLOCK) titled by the header Line "Look! — new Note unlocked"; each unlock appends a per-event Line ("Stargazer, 5:21:00 PM") + spawns a Brief FK'd to that Line.

Server:
- billboard.Post gains a `kind` enum (NOTE_UNLOCK / USER_POST / SHARE_INVITE, default USER_POST) so the per-category Post is deterministically discoverable via (owner, kind=NOTE_UNLOCK).
- drama.Note.grant_if_new now returns (note, created, brief) — backwards-incompat tuple shape; the new third slot is None on idempotent re-grants. On a fresh grant it: get-or-creates the user's Note Unlocks Post; ensures the header Line; appends a per-event Line w. timestamp; creates a Brief(kind=NOTE_UNLOCK, owner, post, line, title=note.display_title).
- dashboard.views.sky_save's response shape flips {note: {...}|null} → {brief: {...}|null}. The new helper _brief_to_banner_dict exposes {id, kind, title, line_text, post_url, square_url, created_at}; for NOTE_UNLOCK kind, square_url = reverse('billboard:my_notes').

Banner JS (apps/dashboard/note.js):
- Module renamed Note → Brief (Note kept as an alias during the C3 sprint; will retire in C3.e). showBanner now consumes the Brief shape: title from brief.title, body from brief.line_text, time from brief.created_at, FYI href = brief.post_url, NVM dismisses, .note-banner__image is rendered as a clickable <a href=brief.square_url> when square_url is set. The CSS class names (.note-banner, .note-banner__title, etc.) stay so all existing SCSS + FT selectors keep working.
- sky.html + _applet-my-sky.html flip Note.handleSaveResponse → Brief.handleSaveResponse.

Tests:
- new IT class GrantIfNewSpawnsBriefTest (5 tests): first grant creates Post+Line+Brief, idempotent on second grant returns no brief, two different slugs share one Post, line text carries note title, post.kind == NOTE_UNLOCK. PostKindFieldTest (2 tests): default user_post + all three choices present.
- existing drama test_models.GrantIfNew tests updated to unpack the third tuple element.
- dashboard.tests.integrated.test_sky_views: 5 tests flipped from data["note"] → data["brief"] w/ the new payload shape (kind=note_unlock, title=Stargazer, line_text contains Stargazer, post_url under /billboard/post/, square_url=/billboard/my-notes/).
- NoteSpec.js (Jasmine): 12 specs rewritten for the Brief shape — SAMPLE_BRIEF carries the seven fields, T6 asserts the square is a clickable <a>, T8 asserts FYI points at brief.post_url (was hardcoded /billboard/my-notes/).
- functional_tests.test_applet_my_notes: T2 split — FYI now navigates to /billboard/post/<uuid>/ (the post detail / mark-read contract), the .note-banner__image square preserves the legacy jump direct to /billboard/my-notes/.

billboard/0003_post_kind migration auto-generated. 808 ITs + 9 my_notes FTs + 1 Jasmine FT all green.

Code architected by Disco DeDisco <discodedisco@outlook.com>
Git commit message Co-Authored-By:
Claude Sonnet 4.6 <noreply@anthropic.com>

src/apps/dashboard/tests/integrated/test_sky_views.py

@@ -272,23 +272,25 @@ class SkySaveNoteTest(TestCase):
             content_type="application/json",
         )
 
-    def test_first_save_with_chart_data_returns_stargazer_note(self):
+    def test_first_save_with_chart_data_returns_stargazer_brief(self):
         data = self._post().json()
-        self.assertIn("note", data)
-        recog = data["note"]
-        self.assertEqual(recog["slug"], "stargazer")
-        self.assertIn("title", recog)
-        self.assertIn("description", recog)
-        self.assertIn("earned_at", recog)
+        self.assertIn("brief", data)
+        brief = data["brief"]
+        self.assertEqual(brief["kind"], "note_unlock")
+        self.assertEqual(brief["title"], "Stargazer")
+        self.assertIn("Stargazer", brief["line_text"])
+        self.assertIn("/billboard/post/", brief["post_url"])
+        self.assertEqual(brief["square_url"], "/billboard/my-notes/")
+        self.assertIn("created_at", brief)
 
     def test_first_save_creates_note_in_db(self):
         self._post()
         self.assertEqual(Note.objects.filter(user=self.user, slug="stargazer").count(), 1)
 
-    def test_second_save_returns_null_note(self):
+    def test_second_save_returns_null_brief(self):
         self._post()
         data = self._post().json()
-        self.assertIsNone(data["note"])
+        self.assertIsNone(data["brief"])
 
     def test_second_save_does_not_create_duplicate_note(self):
         self._post()
@@ -297,12 +299,12 @@ class SkySaveNoteTest(TestCase):
 
     def test_save_with_empty_chart_data_does_not_grant_note(self):
         data = self._post(chart_data={}).json()
-        self.assertIsNone(data["note"])
+        self.assertIsNone(data["brief"])
         self.assertEqual(Note.objects.filter(user=self.user, slug="stargazer").count(), 0)
 
     def test_save_with_null_chart_data_does_not_grant_note(self):
         data = self._post(chart_data=None).json()
-        self.assertIsNone(data["note"])
+        self.assertIsNone(data["brief"])
         self.assertEqual(Note.objects.filter(user=self.user, slug="stargazer").count(), 0)