feat: add gettext i18n with translations (vi, de, fr, it, es, pt)

Wire up internationalization for the app and ship six translations.

Infrastructure:
- meson: import i18n, define GETTEXT_PACKAGE/GSR_LOCALEDIR, add po/ subdir,
  and translate the .desktop and AppStream metainfo via i18n.merge_file
  (renamed to .desktop.in / .metainfo.xml.in).
- main.c: setlocale + bindtextdomain/textdomain so the catalog is loaded.
- po/: LINGUAS, POTFILES.in, meson.build (glib preset).

String marking:
- Wrap every user-visible string with _() across main.c, gsr-window.c, the four
  pages and the shortcut dialog (titles, subtitles, labels, buttons, combo
  display names, notifications, toasts, dialogs, menu items).
- Leave ids/keys untranslated: codec/container/service ids, GAction/icon/CSS
  names, GVariant/format strings, accelerators, etc.

Linting:
- Re-enable gobject-linter's untranslated_string rule (now that i18n exists) as
  an error so new user-visible strings must be wrapped.

Translations (141 messages each, %s/%d/markup placeholders preserved):
- Vietnamese (vi), German (de), French (fr), Italian (it), Spanish (es),
  Portuguese (pt). Codec names, "OK", proper nouns and the product name are
  intentionally left in English. Verified: msgfmt --check-format passes and the
  compiled catalogs resolve (e.g. "Record" -> "Ghi hình" / "Aufnahme" /
  "Enregistrement").

1 files changed, 28 insertions, 26 deletions

diff --git a/src/gsr-record-page.c b/src/gsr-record-page.c
index 745bdcf..40b28bb 100644
--- a/src/gsr-record-page.c
+++ b/src/gsr-record-page.c
@@ -3,6 +3,8 @@
 #include <signal.h>
 #include <time.h>
 
+#include <glib/gi18n.h>
+
 #include "gsr-window.h"
 
 #ifdef HAVE_X11
@@ -131,7 +133,7 @@ on_save_dir_activated(AdwActionRow *row G_GNUC_UNUSED,
 {
     GsrRecordPage *self = GSR_RECORD_PAGE(user_data);
     g_autoptr(GtkFileDialog) dialog = gtk_file_dialog_new();
-    gtk_file_dialog_set_title(dialog, "Select save directory");
+    gtk_file_dialog_set_title(dialog, _("Select save directory"));
 
     if (self->save_directory) {
         g_autoptr(GFile) initial = g_file_new_for_path(self->save_directory);
@@ -247,7 +249,7 @@ on_x11_start_stop_activated(AdwActionRow *row G_GNUC_UNUSED,
 {
     GsrRecordPage *self = GSR_RECORD_PAGE(user_data);
     GsrShortcutAccelDialog *dialog = gsr_shortcut_accel_dialog_new(
-        "Start/Stop recording", self->x11_start_stop_accel);
+        _("Start/Stop recording"), self->x11_start_stop_accel);
     g_signal_connect(dialog, "shortcut-set",
         G_CALLBACK(on_x11_start_stop_shortcut_set), self);
     adw_dialog_present(ADW_DIALOG(dialog), GTK_WIDGET(self));
@@ -278,7 +280,7 @@ on_x11_pause_activated(AdwActionRow *row G_GNUC_UNUSED,
 {
     GsrRecordPage *self = GSR_RECORD_PAGE(user_data);
     GsrShortcutAccelDialog *dialog = gsr_shortcut_accel_dialog_new(
-        "Pause/Unpause recording", self->x11_pause_accel);
+        _("Pause/Unpause recording"), self->x11_pause_accel);
     g_signal_connect(dialog, "shortcut-set",
         G_CALLBACK(on_x11_pause_shortcut_set), self);
     adw_dialog_present(ADW_DIALOG(dialog), GTK_WIDGET(self));
@@ -289,7 +291,7 @@ static void
 build_hotkey_group(GsrRecordPage *self)
 {
     self->hotkey_group = ADW_PREFERENCES_GROUP(adw_preferences_group_new());
-    adw_preferences_group_set_title(self->hotkey_group, "Hotkeys");
+    adw_preferences_group_set_title(self->hotkey_group, _("Hotkeys"));
 
     GsrDisplayServer ds = self->info->system_info.display_server;
 
@@ -297,8 +299,8 @@ build_hotkey_group(GsrRecordPage *self)
     if (ds == GSR_DISPLAY_SERVER_WAYLAND) {
         /* "Not supported" label — initially hidden, shown if portal fails */
         self->hotkey_not_supported_label = gtk_label_new(
-            "Your Wayland compositor doesn't support global hotkeys.\n"
-            "Use X11 or KDE Plasma on Wayland if you want to use hotkeys.");
+            _("Your Wayland compositor doesn't support global hotkeys.\n"
+            "Use X11 or KDE Plasma on Wayland if you want to use hotkeys."));
         gtk_label_set_wrap(GTK_LABEL(self->hotkey_not_supported_label), TRUE);
         gtk_widget_add_css_class(self->hotkey_not_supported_label, "dim-label");
         gtk_widget_set_margin_top(self->hotkey_not_supported_label, 6);
@@ -312,32 +314,32 @@ build_hotkey_group(GsrRecordPage *self)
         self->hotkey_info_row = GTK_WIDGET(info_row);
         if (is_kde_wayland()) {
             adw_preferences_row_set_title(ADW_PREFERENCES_ROW(info_row),
-                "Hotkeys are managed by KDE Plasma");
+                _("Hotkeys are managed by KDE Plasma"));
             adw_action_row_set_subtitle(info_row,
-                "Click to configure hotkeys in system settings");
+                _("Click to configure hotkeys in system settings"));
             GtkButton *change_btn = GTK_BUTTON(
-                gtk_button_new_with_label("Change hotkeys"));
+                gtk_button_new_with_label(_("Change hotkeys")));
             gtk_widget_set_valign(GTK_WIDGET(change_btn), GTK_ALIGN_CENTER);
             g_object_set_data(G_OBJECT(info_row), "change-button", change_btn);
             adw_action_row_add_suffix(info_row, GTK_WIDGET(change_btn));
         } else {
             adw_preferences_row_set_title(ADW_PREFERENCES_ROW(info_row),
-                "Hotkeys are managed by your compositor");
+                _("Hotkeys are managed by your compositor"));
             adw_action_row_set_subtitle(info_row,
-                "Go to system settings to change hotkeys");
+                _("Go to system settings to change hotkeys"));
         }
         adw_preferences_group_add(self->hotkey_group, GTK_WIDGET(info_row));
 
         /* Hotkey labels (shown after portal succeeds) */
         AdwActionRow *start_row = ADW_ACTION_ROW(adw_action_row_new());
         adw_preferences_row_set_title(ADW_PREFERENCES_ROW(start_row),
-            "Start/Stop recording");
+            _("Start/Stop recording"));
         adw_action_row_set_subtitle(start_row, "");
         adw_preferences_group_add(self->hotkey_group, GTK_WIDGET(start_row));
 
         AdwActionRow *pause_row = ADW_ACTION_ROW(adw_action_row_new());
         adw_preferences_row_set_title(ADW_PREFERENCES_ROW(pause_row),
-            "Pause/Unpause recording");
+            _("Pause/Unpause recording"));
         adw_action_row_set_subtitle(pause_row, "");
         adw_preferences_group_add(self->hotkey_group, GTK_WIDGET(pause_row));
 
@@ -353,7 +355,7 @@ build_hotkey_group(GsrRecordPage *self)
         /* X11: interactive shortcut rows */
         self->x11_start_stop_row = ADW_ACTION_ROW(adw_action_row_new());
         adw_preferences_row_set_title(ADW_PREFERENCES_ROW(self->x11_start_stop_row),
-            "Start/Stop recording");
+            _("Start/Stop recording"));
         gtk_list_box_row_set_activatable(GTK_LIST_BOX_ROW(self->x11_start_stop_row), TRUE);
 
         self->x11_start_stop_label = GTK_SHORTCUT_LABEL(
@@ -372,7 +374,7 @@ build_hotkey_group(GsrRecordPage *self)
         /* Pause/Unpause row */
         self->x11_pause_row = ADW_ACTION_ROW(adw_action_row_new());
         adw_preferences_row_set_title(ADW_PREFERENCES_ROW(self->x11_pause_row),
-            "Pause/Unpause recording");
+            _("Pause/Unpause recording"));
         gtk_list_box_row_set_activatable(GTK_LIST_BOX_ROW(self->x11_pause_row), TRUE);
 
         self->x11_pause_label = GTK_SHORTCUT_LABEL(
@@ -399,13 +401,13 @@ static void
 build_output_group(GsrRecordPage *self)
 {
     self->output_group = ADW_PREFERENCES_GROUP(adw_preferences_group_new());
-    adw_preferences_group_set_title(self->output_group, "Output");
+    adw_preferences_group_set_title(self->output_group, _("Output"));
 
     /* Save directory */
     self->save_directory = get_default_videos_dir();
     self->save_dir_row = ADW_ACTION_ROW(adw_action_row_new());
     adw_preferences_row_set_title(ADW_PREFERENCES_ROW(self->save_dir_row),
-        "Save directory");
+        _("Save directory"));
     adw_action_row_set_subtitle(self->save_dir_row, self->save_directory);
     gtk_list_box_row_set_activatable(GTK_LIST_BOX_ROW(self->save_dir_row), TRUE);
 
@@ -421,7 +423,7 @@ build_output_group(GsrRecordPage *self)
     /* Container format */
     self->container_row = ADW_COMBO_ROW(adw_combo_row_new());
     adw_preferences_row_set_title(ADW_PREFERENCES_ROW(self->container_row),
-        "Container");
+        _("Container"));
 
     GtkStringList *ct_model = gtk_string_list_new(NULL);
     const char *containers[] = {
@@ -453,7 +455,7 @@ build_action_group(GsrRecordPage *self)
     gtk_widget_set_margin_bottom(GTK_WIDGET(box), 6);
 
     self->start_button = GTK_BUTTON(
-        gtk_button_new_with_label("Start recording"));
+        gtk_button_new_with_label(_("Start recording")));
     gtk_widget_set_hexpand(GTK_WIDGET(self->start_button), TRUE);
     gtk_widget_add_css_class(GTK_WIDGET(self->start_button), "suggested-action");
     g_signal_connect(self->start_button, "clicked",
@@ -461,7 +463,7 @@ build_action_group(GsrRecordPage *self)
     gtk_box_append(box, GTK_WIDGET(self->start_button));
 
     self->pause_button = GTK_BUTTON(
-        gtk_button_new_with_label("Pause recording"));
+        gtk_button_new_with_label(_("Pause recording")));
     gtk_widget_set_hexpand(GTK_WIDGET(self->pause_button), TRUE);
     gtk_widget_set_sensitive(GTK_WIDGET(self->pause_button), FALSE);
     g_signal_connect(self->pause_button, "clicked",
@@ -628,7 +630,7 @@ void
 gsr_record_page_set_active(GsrRecordPage *self, gboolean active)
 {
     if (active) {
-        gtk_button_set_label(self->start_button, "Stop recording");
+        gtk_button_set_label(self->start_button, _("Stop recording"));
         gtk_widget_remove_css_class(GTK_WIDGET(self->start_button), "suggested-action");
         gtk_widget_add_css_class(GTK_WIDGET(self->start_button), "destructive-action");
         gtk_widget_set_sensitive(GTK_WIDGET(self->pause_button), TRUE);
@@ -636,11 +638,11 @@ gsr_record_page_set_active(GsrRecordPage *self, gboolean active)
         gtk_widget_add_css_class(GTK_WIDGET(self->record_icon), "recording-active");
         gtk_widget_remove_css_class(GTK_WIDGET(self->record_icon), "recording-paused");
     } else {
-        gtk_button_set_label(self->start_button, "Start recording");
+        gtk_button_set_label(self->start_button, _("Start recording"));
         gtk_widget_remove_css_class(GTK_WIDGET(self->start_button), "destructive-action");
         gtk_widget_add_css_class(GTK_WIDGET(self->start_button), "suggested-action");
         gtk_widget_set_sensitive(GTK_WIDGET(self->pause_button), FALSE);
-        gtk_button_set_label(self->pause_button, "Pause recording");
+        gtk_button_set_label(self->pause_button, _("Pause recording"));
         gtk_widget_set_opacity(GTK_WIDGET(self->status_box), 0.5);
         gtk_label_set_text(self->timer_label, "00:00:00");
         gtk_image_set_from_icon_name(self->record_icon, "media-record-symbolic");
@@ -658,12 +660,12 @@ void
 gsr_record_page_set_paused(GsrRecordPage *self, gboolean paused)
 {
     if (paused) {
-        gtk_button_set_label(self->pause_button, "Unpause recording");
+        gtk_button_set_label(self->pause_button, _("Unpause recording"));
         gtk_image_set_from_icon_name(self->record_icon, "media-playback-pause-symbolic");
         gtk_widget_remove_css_class(GTK_WIDGET(self->record_icon), "recording-active");
         gtk_widget_add_css_class(GTK_WIDGET(self->record_icon), "recording-paused");
     } else {
-        gtk_button_set_label(self->pause_button, "Pause recording");
+        gtk_button_set_label(self->pause_button, _("Pause recording"));
         gtk_image_set_from_icon_name(self->record_icon, "media-record-symbolic");
         gtk_widget_remove_css_class(GTK_WIDGET(self->record_icon), "recording-paused");
         gtk_widget_add_css_class(GTK_WIDGET(self->record_icon), "recording-active");
@@ -697,7 +699,7 @@ gsr_record_page_new(const GsrInfo *info)
     GsrRecordPage *self = g_object_new(GSR_TYPE_RECORD_PAGE, NULL);
     self->info = info;
 
-    adw_preferences_page_set_title(ADW_PREFERENCES_PAGE(self), "Record");
+    adw_preferences_page_set_title(ADW_PREFERENCES_PAGE(self), _("Record"));
     adw_preferences_page_set_icon_name(ADW_PREFERENCES_PAGE(self),
         "media-record-symbolic");