feat(workspace): bring an extracted note back into the bullet

A bullet that is only a link to a note (as left by /extract) gets a
"Notiz zurückholen" button. POST /documents/{id}/inline returns the
linked note's blocks with fresh ids and trashes the note; the editor
puts the title back as text and inserts the blocks as an own edit, so
Strg+Z restores the link and the note. Only own notes that no other
note links to. Release 0.52.0.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/api/restructure_test.go

@@ -186,3 +186,79 @@ func TestMergeDocumentsAndUndo(t *testing.T) {
 		t.Fatalf("foreign source: want 403, got %d %s", rec.Code, rec.Body.String())
 	}
 }
+
+// The way back from extracting: the link bullet gets the note's blocks, the note goes to the trash.
+func TestInlineNoteBringsBranchBack(t *testing.T) {
+	srv, store, token := setupTestServer(t)
+	router := srv.Router()
+	claims, _ := auth.ValidateToken(testJWTSecret, token)
+	uid := claims.UserID
+	note, _ := store.CreateDocument(uid, "", "Konzept: Garten", "", "", []domain.DocumentBlock{
+		{ID: "blk_b", Type: "bullet", Content: "Beete", Level: 0, Position: 1},
+		{ID: "blk_c", Type: "todo", Content: "Erde kaufen", Level: 1, Position: 2, Checked: true},
+		{ID: "blk_d", Type: "bullet", Content: "Zaun", Level: 0, Position: 3},
+	}, nil, false)
+	src, _ := store.CreateDocument(uid, "", "Projekt", "", "", []domain.DocumentBlock{
+		{ID: "blk_l", Type: "bullet", Content: "[[konzept: garten]] #draußen", Level: 0, Position: 1},
+		{ID: "blk_t", Type: "bullet", Content: "Siehe [[Konzept: Garten]]", Level: 0, Position: 2},
+		{ID: "blk_x", Type: "bullet", Content: "[[Gibt es nicht]]", Level: 0, Position: 3},
+	}, nil, false)
+	inline := func(docID, blockID, tok string) (int, storage.InlineResult) {
+		rec := sessionCall(router, "POST", "/api/v1/documents/"+docID+"/inline", tok, `{"blockId":"`+blockID+`"}`, "")
+		var out storage.InlineResult
+		_ = json.Unmarshal(rec.Body.Bytes(), &out)
+		return rec.Code, out
+	}
+	if code, _ := inline(src.ID, "blk_t", token); code != http.StatusBadRequest {
+		t.Fatalf("text with a link is no link bullet: %d", code)
+	}
+	if code, _ := inline(src.ID, "blk_x", token); code != http.StatusNotFound {
+		t.Fatalf("missing note: %d", code)
+	}
+
+	// Linked from another note as well: refused, nothing changes
+	other, _ := store.CreateDocument(uid, "", "Anderswo", "", "", []domain.DocumentBlock{
+		{ID: "blk_o", Type: "bullet", Content: "auch [[Konzept: Garten]]", Level: 0, Position: 1},
+	}, nil, false)
+	if code, _ := inline(src.ID, "blk_l", token); code != http.StatusConflict {
+		t.Fatalf("note linked elsewhere must be refused: %d", code)
+	}
+	if d, _ := store.GetDocumentByID(uid, note.ID); d.IsArchived {
+		t.Fatal("refused inline must not trash the note")
+	}
+	if rec := sessionCall(router, "DELETE", "/api/v1/documents/"+other.ID, token, "", ""); rec.Code >= 300 {
+		t.Fatalf("delete other: %d", rec.Code)
+	}
+
+	// Another person's note cannot be pulled in, even when shared with write access
+	stranger, strangerToken := newTestUser(t, store, "fremd3@example.com")
+	openSharing(t, store)
+	if _, err := store.CreateDocShare(uid, src.ID, stranger.Email, "write"); err != nil {
+		t.Fatal(err)
+	}
+	if code, _ := inline(src.ID, "blk_l", strangerToken); code != http.StatusForbidden && code != http.StatusNotFound {
+		t.Fatalf("stranger must not pull in someone else's note: %d", code)
+	}
+
+	code, res := inline(src.ID, "blk_l", token)
+	if code != http.StatusOK || res.SourceID != note.ID || res.Content != "Konzept: Garten #draußen" {
+		t.Fatalf("inline: %d %+v", code, res)
+	}
+	var got []string
+	for _, b := range res.Blocks {
+		got = append(got, strings.Repeat(">", b.Level)+b.Content)
+		if b.ID == "blk_b" || b.ID == "blk_c" {
+			t.Fatal("blocks need fresh ids, the old ones live on in the trashed note")
+		}
+	}
+	if strings.Join(got, "|") != "Beete|>Erde kaufen|Zaun" || !res.Blocks[1].Checked || res.Blocks[1].Type != "todo" {
+		t.Fatalf("blocks: %v %+v", got, res.Blocks)
+	}
+	if d, _ := store.GetDocumentByID(uid, note.ID); d == nil || !d.IsArchived {
+		t.Fatal("brought-back note must be in the trash")
+	}
+	// Undo uses the ordinary restore
+	if rec := sessionCall(router, "POST", "/api/v1/documents/"+note.ID+"/restore", token, "", ""); rec.Code != http.StatusOK {
+		t.Fatalf("restore: %d %s", rec.Code, rec.Body.String())
+	}
+}