Admin: add title field, live preview, and delete; DB migration for title; show title in list; keep Admin button on public pages

app.py

@@ -53,11 +53,19 @@ def create_app():
             CREATE TABLE IF NOT EXISTS pages (
                 id INTEGER PRIMARY KEY AUTOINCREMENT,
                 uuid TEXT NOT NULL UNIQUE,
+                title TEXT NOT NULL DEFAULT '',
                 html TEXT NOT NULL,
                 created_at TEXT NOT NULL
             );
             """
         )
+        # Migration: add 'title' column for older DB versions
+        try:
+            cols = {row[1] for row in db.execute("PRAGMA table_info(pages)").fetchall()}
+            if "title" not in cols:
+                db.execute("ALTER TABLE pages ADD COLUMN title TEXT NOT NULL DEFAULT ''")
+        except Exception:
+            pass
         db.commit()
 
     @app.before_request
@@ -120,29 +128,42 @@ def create_app():
         login_required()
         db = get_db()
         if request.method == "POST":
+            title = request.form.get("title", "").strip()
             html = request.form.get("html", "").strip()
             if not html:
                 flash("HTML не может быть пустым.", "error")
             else:
                 uid = uuid_lib.uuid4().hex
                 db.execute(
-                    "INSERT INTO pages (uuid, html, created_at) VALUES (?, ?, ?)",
-                    (uid, html, datetime.utcnow().isoformat(timespec="seconds")),
+                    "INSERT INTO pages (uuid, title, html, created_at) VALUES (?, ?, ?, ?)",
+                    (uid, title, html, datetime.utcnow().isoformat(timespec="seconds")),
                 )
                 db.commit()
                 flash("Страница опубликована.", "success")
                 return redirect(url_for("admin"))
 
         pages = db.execute(
-            "SELECT id, uuid, created_at FROM pages ORDER BY id DESC"
+            "SELECT id, uuid, title, created_at FROM pages ORDER BY id DESC"
         ).fetchall()
         base_url = request.host_url.rstrip("/")
         return render_template("admin.html", pages=pages, base_url=base_url)
 
+    @app.route("/admin/delete/<int:pid>", methods=["POST"])
+    def admin_delete(pid: int):
+        login_required()
+        db = get_db()
+        cur = db.execute("DELETE FROM pages WHERE id = ?", (pid,))
+        db.commit()
+        if cur.rowcount:
+            flash("Страница удалена.", "success")
+        else:
+            flash("Страница не найдена.", "error")
+        return redirect(url_for("admin"))
+
     @app.route("/p/<string:uid>")
     def view_page(uid: str):
         db = get_db()
-        row = db.execute("SELECT html FROM pages WHERE uuid = ?", (uid,)).fetchone()
+        row = db.execute("SELECT html, title FROM pages WHERE uuid = ?", (uid,)).fetchone()
         if row is None:
             abort(404)
         # Show a floating admin button for authenticated users, otherwise serve raw HTML