chore: stage all pending work — caption styling, media server, processing modal, docs, summaries

Includes:
- Extended caption styling (font, shadow, dimmed color, bg toggle)
- Media server, subtitle downloader, VTT parser, processing modal
- Waveform tiers, thumbnail/timeline improvements, transport controls
- Hybrid download model, dependency management, clip export enhancements
- 21 chat summaries, 2 implementation plans, 2 design specs

Co-authored-by: Cursor <cursoragent@cursor.com>

src-tauri/src/services/video_resolver.rs

@@ -1,13 +1,56 @@
 use crate::models::{CookieSource, VideoMetadata};
 use serde::Deserialize;
+use std::collections::HashMap;
 use std::process::Command;
 
+#[derive(Debug, Deserialize)]
+pub struct SubtitleFormat {
+    pub ext: Option<String>,
+    pub url: Option<String>,
+}
+
 #[derive(Debug, Deserialize)]
 pub struct YtDlpJson {
     pub title: String,
     pub duration: Option<f64>,
     pub fps: Option<f64>,
     pub thumbnail: Option<String>,
+    /// Manually authored subtitles: language_code -> [formats]
+    #[serde(default)]
+    pub subtitles: HashMap<String, Vec<SubtitleFormat>>,
+    /// Auto-generated subtitles: language_code -> [formats]
+    #[serde(default)]
+    pub automatic_captions: HashMap<String, Vec<SubtitleFormat>>,
+}
+
+/// Check if subtitles have a VTT format for English (en, en-US, en-GB, en-orig).
+fn find_english_key(map: &HashMap<String, Vec<SubtitleFormat>>) -> Option<&str> {
+    // Prefer exact "en", then any en-* variant
+    for key in ["en", "en-US", "en-GB", "en-orig"] {
+        if map.contains_key(key) {
+            return Some(key);
+        }
+    }
+    // Try any key starting with "en"
+    for key in map.keys() {
+        if key.starts_with("en") {
+            return Some(key.as_str());
+        }
+    }
+    None
+}
+
+/// Determine caption availability: (has_captions, is_auto)
+pub fn detect_captions(meta: &YtDlpJson) -> (bool, bool) {
+    // Priority 1: manual English subtitles
+    if find_english_key(&meta.subtitles).is_some() {
+        return (true, false);
+    }
+    // Priority 2: auto-generated English captions
+    if find_english_key(&meta.automatic_captions).is_some() {
+        return (true, true);
+    }
+    (false, false)
 }
 
 pub fn parse_ytdlp_json(json_str: &str) -> Result<YtDlpJson, String> {
@@ -41,6 +84,8 @@ pub fn resolve(url: &str, cookie_source: &CookieSource) -> Result<VideoMetadata,
     let json_str = String::from_utf8_lossy(&meta_output.stdout);
     let meta = parse_ytdlp_json(&json_str)?;
 
+    let (has_captions, captions_are_auto) = detect_captions(&meta);
+
     let mut stream_cmd = Command::new("yt-dlp");
     stream_cmd
         .arg("-g")
@@ -79,6 +124,8 @@ pub fn resolve(url: &str, cookie_source: &CookieSource) -> Result<VideoMetadata,
         fps: meta.fps.unwrap_or(30.0),
         thumbnail_url: meta.thumbnail,
         stream_url,
+        has_captions,
+        captions_are_auto,
     })
 }
 
@@ -107,6 +154,8 @@ mod tests {
         assert!(result.duration.is_none());
         assert!(result.fps.is_none());
         assert!(result.thumbnail.is_none());
+        assert!(result.subtitles.is_empty());
+        assert!(result.automatic_captions.is_empty());
     }
 
     #[test]
@@ -114,4 +163,39 @@ mod tests {
         let result = parse_ytdlp_json("not json");
         assert!(result.is_err());
     }
+
+    #[test]
+    fn test_detect_captions_manual() {
+        let json = r#"{"title": "T", "subtitles": {"en": [{"ext": "vtt", "url": "http://x"}]}, "automatic_captions": {}}"#;
+        let meta = parse_ytdlp_json(json).unwrap();
+        let (has, is_auto) = detect_captions(&meta);
+        assert!(has);
+        assert!(!is_auto);
+    }
+
+    #[test]
+    fn test_detect_captions_auto_only() {
+        let json = r#"{"title": "T", "subtitles": {}, "automatic_captions": {"en": [{"ext": "vtt", "url": "http://x"}]}}"#;
+        let meta = parse_ytdlp_json(json).unwrap();
+        let (has, is_auto) = detect_captions(&meta);
+        assert!(has);
+        assert!(is_auto);
+    }
+
+    #[test]
+    fn test_detect_captions_none() {
+        let json = r#"{"title": "T"}"#;
+        let meta = parse_ytdlp_json(json).unwrap();
+        let (has, _) = detect_captions(&meta);
+        assert!(!has);
+    }
+
+    #[test]
+    fn test_detect_captions_en_variant() {
+        let json = r#"{"title": "T", "subtitles": {"en-US": [{"ext": "vtt"}]}}"#;
+        let meta = parse_ytdlp_json(json).unwrap();
+        let (has, is_auto) = detect_captions(&meta);
+        assert!(has);
+        assert!(!is_auto);
+    }
 }