ui: add AnimationMode to control GIF rendering behavior

Introduces an `AnimationMode` enum with `Reactive`, `Continuous`, and
`NoAnimation` variants to allow fine-grained control over GIF playback
across the UI. This supports performance optimizations and accessibility
features, such as disabling animations when requested.

- Plumbs AnimationMode through image rendering paths
- Replaces hardcoded gif frame logic with reusable `process_gif_frame`
- Supports customizable FPS in Continuous mode
- Enables global animation opt-out via `NoteOptions::NoAnimations`
- Applies mode-specific logic in profile pictures, posts, media carousels, and viewer

Animation behavior by context
-----------------------------

- Profile pictures: Reactive (render only on interaction/activity)
- PostView: NoAnimation if disabled in NoteOptions, else Continuous (uncapped)
- Media carousels: NoAnimation or Continuous (capped at 24fps)
- Viewer/gallery: Always Continuous (full animation)

In the future, we can customize these by power settings.

Signed-off-by: William Casarin <jb55@jb55.com>

crates/notedeck_ui/src/note/media.rs

@@ -13,6 +13,7 @@ use notedeck::{
 use crate::NoteOptions;
 use notedeck::media::gif::ensure_latest_texture;
 use notedeck::media::images::{fetch_no_pfp_promise, ImageType};
+use notedeck::media::AnimationMode;
 use notedeck::media::{MediaInfo, ViewMediaInfo};
 
 use crate::{app_images, AnimationHelper, PulseAlpha};
@@ -82,6 +83,18 @@ pub fn image_carousel(
                                 blur_type,
                             );
 
+                            let animation_mode = if note_options.contains(NoteOptions::NoAnimations)
+                            {
+                                AnimationMode::NoAnimation
+                            } else {
+                                // if animations aren't disabled, we cap it at 24fps for gifs in carousels
+                                let fps = match media_type {
+                                    MediaCacheType::Gif => Some(24.0),
+                                    MediaCacheType::Image => None,
+                                };
+                                AnimationMode::Continuous { fps }
+                            };
+
                             let media_response = render_media(
                                 ui,
                                 &mut img_cache.gif_states,
@@ -90,6 +103,7 @@ pub fn image_carousel(
                                 size,
                                 i18n,
                                 note_options.contains(NoteOptions::Wide),
+                                animation_mode,
                             );
 
                             if let Some(action) = media_response.inner {
@@ -324,10 +338,12 @@ fn render_media(
     size: egui::Vec2,
     i18n: &mut Localization,
     is_scaled: bool,
+    animation_mode: AnimationMode,
 ) -> egui::InnerResponse<Option<MediaUIAction>> {
     match render_state {
         MediaRenderState::ActualImage(image) => {
-            let resp = render_success_media(ui, url, image, gifs, size, i18n, is_scaled);
+            let resp =
+                render_success_media(ui, url, image, gifs, size, i18n, is_scaled, animation_mode);
             if resp.clicked() {
                 egui::InnerResponse::new(Some(MediaUIAction::Clicked), resp)
             } else {
@@ -559,6 +575,7 @@ pub(crate) fn find_renderable_media<'a>(
 }
 */
 
+#[allow(clippy::too_many_arguments)]
 fn render_success_media(
     ui: &mut egui::Ui,
     url: &str,
@@ -567,8 +584,9 @@ fn render_success_media(
     size: Vec2,
     i18n: &mut Localization,
     is_scaled: bool,
+    animation_mode: AnimationMode,
 ) -> Response {
-    let texture = ensure_latest_texture(ui, url, gifs, tex);
+    let texture = ensure_latest_texture(ui, url, gifs, tex, animation_mode);
 
     let scaled = ScaledTexture::new(&texture, size, is_scaled);
 

crates/notedeck_ui/src/note/options.rs

@@ -35,6 +35,9 @@ bitflags! {
 
         /// Note has an unread reply indicator
         const UnreadIndicator = 1 << 16;
+
+        /// no animation override (accessibility)
+        const NoAnimations = 1 << 17;
     }
 }