Fix bugs across app + server, optimize UI/UX, add Gitea CI

Bug fixes (Flutter):
- Wrap multi-statement DB writes (insert/update/delete note, deleteDocument,
  deletePageData, OCR FTS merge, migrations) in transactions to prevent data
  loss on interruption and a read-modify-write FTS race.
- Fix PdfDocument leaks on exception (try/finally dispose) and preserve image
  aspect ratio when stamping images onto PDF pages.
- Guard file-picker against empty selection (was .single -> crash).
- Fix eraser ConcurrentModificationError and unmodifiable-list crash on PDF
  pages; capture page synchronously on save to stop wrong-page data loss.
- Fix Riverpod DB-not-ready races, broken pull-to-refresh, settings load race,
  and search N+1; transform stored annotations on PDF page rotation.
- Normalize pen pressure for devices without a pressure range.
- PPT: single source of truth for slide strokes so ink displays and exports.

UI/UX:
- Material 3 typography, theme-aware colors (dark-mode fixes), hover cursors
  and right-click/visible actions on desktop, keyboard shortcuts (undo/redo/
  save/find), toolbar overflow handling, friendlier empty states, semantic OCR
  status badges, relative timestamps, 1-based page indicators, large-deck PPT
  navigation, and a scratchpad-scope label in split view.

Server (optional backend):
- Persist JWT secret (was per-process random), block path traversal in storage,
  fix CORS '*'+credentials, add OCR job ownership checks, last-writer-wins sync
  guard, constant-time login, and split out heavy OCR deps so the API/tests run
  without them.

CI: Gitea workflows for format+analyze+test (Linux, system sqlite) and a
Windows release build; pristine `flutter analyze`, all Flutter and server tests
green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

linux/runner/my_application.cc

@@ -0,0 +1,148 @@
+#include "my_application.h"
+
+#include <flutter_linux/flutter_linux.h>
+#ifdef GDK_WINDOWING_X11
+#include <gdk/gdkx.h>
+#endif
+
+#include "flutter/generated_plugin_registrant.h"
+
+struct _MyApplication {
+  GtkApplication parent_instance;
+  char** dart_entrypoint_arguments;
+};
+
+G_DEFINE_TYPE(MyApplication, my_application, GTK_TYPE_APPLICATION)
+
+// Called when first Flutter frame received.
+static void first_frame_cb(MyApplication* self, FlView* view) {
+  gtk_widget_show(gtk_widget_get_toplevel(GTK_WIDGET(view)));
+}
+
+// Implements GApplication::activate.
+static void my_application_activate(GApplication* application) {
+  MyApplication* self = MY_APPLICATION(application);
+  GtkWindow* window =
+      GTK_WINDOW(gtk_application_window_new(GTK_APPLICATION(application)));
+
+  // Use a header bar when running in GNOME as this is the common style used
+  // by applications and is the setup most users will be using (e.g. Ubuntu
+  // desktop).
+  // If running on X and not using GNOME then just use a traditional title bar
+  // in case the window manager does more exotic layout, e.g. tiling.
+  // If running on Wayland assume the header bar will work (may need changing
+  // if future cases occur).
+  gboolean use_header_bar = TRUE;
+#ifdef GDK_WINDOWING_X11
+  GdkScreen* screen = gtk_window_get_screen(window);
+  if (GDK_IS_X11_SCREEN(screen)) {
+    const gchar* wm_name = gdk_x11_screen_get_window_manager_name(screen);
+    if (g_strcmp0(wm_name, "GNOME Shell") != 0) {
+      use_header_bar = FALSE;
+    }
+  }
+#endif
+  if (use_header_bar) {
+    GtkHeaderBar* header_bar = GTK_HEADER_BAR(gtk_header_bar_new());
+    gtk_widget_show(GTK_WIDGET(header_bar));
+    gtk_header_bar_set_title(header_bar, "badnote");
+    gtk_header_bar_set_show_close_button(header_bar, TRUE);
+    gtk_window_set_titlebar(window, GTK_WIDGET(header_bar));
+  } else {
+    gtk_window_set_title(window, "badnote");
+  }
+
+  gtk_window_set_default_size(window, 1280, 720);
+
+  g_autoptr(FlDartProject) project = fl_dart_project_new();
+  fl_dart_project_set_dart_entrypoint_arguments(
+      project, self->dart_entrypoint_arguments);
+
+  FlView* view = fl_view_new(project);
+  GdkRGBA background_color;
+  // Background defaults to black, override it here if necessary, e.g. #00000000
+  // for transparent.
+  gdk_rgba_parse(&background_color, "#000000");
+  fl_view_set_background_color(view, &background_color);
+  gtk_widget_show(GTK_WIDGET(view));
+  gtk_container_add(GTK_CONTAINER(window), GTK_WIDGET(view));
+
+  // Show the window when Flutter renders.
+  // Requires the view to be realized so we can start rendering.
+  g_signal_connect_swapped(view, "first-frame", G_CALLBACK(first_frame_cb),
+                           self);
+  gtk_widget_realize(GTK_WIDGET(view));
+
+  fl_register_plugins(FL_PLUGIN_REGISTRY(view));
+
+  gtk_widget_grab_focus(GTK_WIDGET(view));
+}
+
+// Implements GApplication::local_command_line.
+static gboolean my_application_local_command_line(GApplication* application,
+                                                  gchar*** arguments,
+                                                  int* exit_status) {
+  MyApplication* self = MY_APPLICATION(application);
+  // Strip out the first argument as it is the binary name.
+  self->dart_entrypoint_arguments = g_strdupv(*arguments + 1);
+
+  g_autoptr(GError) error = nullptr;
+  if (!g_application_register(application, nullptr, &error)) {
+    g_warning("Failed to register: %s", error->message);
+    *exit_status = 1;
+    return TRUE;
+  }
+
+  g_application_activate(application);
+  *exit_status = 0;
+
+  return TRUE;
+}
+
+// Implements GApplication::startup.
+static void my_application_startup(GApplication* application) {
+  // MyApplication* self = MY_APPLICATION(object);
+
+  // Perform any actions required at application startup.
+
+  G_APPLICATION_CLASS(my_application_parent_class)->startup(application);
+}
+
+// Implements GApplication::shutdown.
+static void my_application_shutdown(GApplication* application) {
+  // MyApplication* self = MY_APPLICATION(object);
+
+  // Perform any actions required at application shutdown.
+
+  G_APPLICATION_CLASS(my_application_parent_class)->shutdown(application);
+}
+
+// Implements GObject::dispose.
+static void my_application_dispose(GObject* object) {
+  MyApplication* self = MY_APPLICATION(object);
+  g_clear_pointer(&self->dart_entrypoint_arguments, g_strfreev);
+  G_OBJECT_CLASS(my_application_parent_class)->dispose(object);
+}
+
+static void my_application_class_init(MyApplicationClass* klass) {
+  G_APPLICATION_CLASS(klass)->activate = my_application_activate;
+  G_APPLICATION_CLASS(klass)->local_command_line =
+      my_application_local_command_line;
+  G_APPLICATION_CLASS(klass)->startup = my_application_startup;
+  G_APPLICATION_CLASS(klass)->shutdown = my_application_shutdown;
+  G_OBJECT_CLASS(klass)->dispose = my_application_dispose;
+}
+
+static void my_application_init(MyApplication* self) {}
+
+MyApplication* my_application_new() {
+  // Set the program name to the application ID, which helps various systems
+  // like GTK and desktop environments map this running application to its
+  // corresponding .desktop file. This ensures better integration by allowing
+  // the application to be recognized beyond its binary name.
+  g_set_prgname(APPLICATION_ID);
+
+  return MY_APPLICATION(g_object_new(my_application_get_type(),
+                                     "application-id", APPLICATION_ID, "flags",
+                                     G_APPLICATION_NON_UNIQUE, nullptr));
+}