agent: dogfood polish 2026/04/19 — Linux native chrome + History redesign + mic picker cleanup

Second dogfood sprint. Headline fix: Linux now uses native KWin/Mutter
decorations instead of fragile frameless `startResizeDragging`, which
collapsed diagonal corner resize to a single axis and made drag feel
laggy. macOS / Windows keep custom chrome via `useCustomChrome` gate.

Other changes:

- Cross-window preferences sync via `kon:preferences-changed` Tauri
  event — theme and font changes propagate live to float/viewer.
- Hotkey recorder rewritten to use capture-phase document listener
  gated by $effect; button focus was unreliable in webkit2gtk.
- History page redesigned for cognitive-load hygiene: title-first
  compact row, inline title input, Edit popout opening /viewer in
  edit mode, clipboard export as .md with YAML frontmatter, manual
  tag chips + + Add tag input, header tag filter (cap 7), global
  Starred filter, `tag:xyz` search syntax.
- `deriveAutoTags` kept as empty hook for post-Task-7 LLM topic tags;
  research found all previous auto-tag chips redundant with row UI.
- Viewer window adds edit mode with debounced-save textarea; native
  title renamed to "Kon - Transcription Editor".
- Window minimums updated per GNOME HIG + WCAG reflow research:
  main 960x600, float 360x480, editor 560x520.
- Microphone picker filters raw ALSA strings (hw:, plughw:, front:,
  sysdefault:, null) and dedupes by CARD=X. New `description` field
  on DeviceInfo reads /proc/asound/cards so Blue Yeti shows as "Blue
  Microphones" instead of the short "Microphones" card name.
- GPU reporting fixed: get_runtime_capabilities now returns
  accelerators=[cpu,vulkan] and whisper.supports_gpu=true, matching
  the transcribe-rs whisper-vulkan feature linked unconditionally.
- ResizeHandles kept for macOS/Windows frameless: 12px edges, 20px
  corners via CSS vars, pointerdown + setPointerCapture, corners
  above edges in z-order, rendered as sibling (not child) of the
  animated layout root so `position: fixed` is viewport-relative.
- Dueling drag-region handlers removed — `data-tauri-drag-region` and
  manual `startDragging()` were stacked on the same elements; kept
  the manual handler which has the button/input early-return logic.

See HANDOVER.md for the full session log and deferred items.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

crates/audio/src/capture.rs

@@ -42,6 +42,11 @@ pub struct DeviceInfo {
     pub is_likely_monitor: bool,
     /// True if cpal reports this as the host's default input device.
     pub is_default: bool,
+    /// Human-readable product description, if known (Linux: from
+    /// `/proc/asound/cards`). Empty string when unavailable or on
+    /// platforms that don't expose one.
+    #[serde(default)]
+    pub description: String,
 }
 
 /// A non-fatal capture-time error emitted by the cpal stream callback after
@@ -97,6 +102,12 @@ impl MicrophoneCapture {
             .input_devices()
             .map_err(|e| KonError::AudioCaptureFailed(format!("input_devices: {e}")))?;
 
+        // Load ALSA card descriptions once per enumeration. These are the
+        // "real" product names (e.g. "Blue Microphones") that cpal's
+        // short card name (e.g. "Microphones") alone can't convey. Empty
+        // map on non-Linux or if the file is missing.
+        let card_descriptions = load_alsa_card_descriptions();
+
         let mut out = Vec::new();
         for device in devices {
             let name = device.name().unwrap_or_else(|_| "<unnamed>".to_string());
@@ -106,12 +117,16 @@ impl MicrophoneCapture {
             };
             let is_likely_monitor = is_monitor_name(&name);
             let is_default = !default_name.is_empty() && name == default_name;
+            let description = extract_card_id(&name)
+                .and_then(|card| card_descriptions.get(card).cloned())
+                .unwrap_or_default();
             out.push(DeviceInfo {
                 name,
                 sample_rate,
                 channels,
                 is_likely_monitor,
                 is_default,
+                description,
             });
         }
         Ok(out)
@@ -252,6 +267,71 @@ fn is_monitor_name(name: &str) -> bool {
         || lower.contains("loopback")
 }
 
+/// Pull the CARD= value from an ALSA device string.
+///
+/// `sysdefault:CARD=Microphones` → `Some("Microphones")`
+/// `hw:CARD=C920,DEV=0`          → `Some("C920")`
+/// `pipewire` / `default`        → `None`
+fn extract_card_id(name: &str) -> Option<&str> {
+    let rest = name.split("CARD=").nth(1)?;
+    Some(rest.split(|c: char| c == ',' || c == ';').next().unwrap_or(rest))
+}
+
+/// Read `/proc/asound/cards` and return a map from ALSA card short name
+/// (e.g. "Microphones") to the richer product string (e.g. "Blue
+/// Microphones"). Empty map on non-Linux or if the file is missing.
+///
+/// Format of `/proc/asound/cards`:
+/// ```text
+///  2 [Microphones    ]: USB-Audio - Blue Microphones
+///                       Blue Microphones at usb-...
+///  3 [C920           ]: USB-Audio - HD Pro Webcam C920
+///                       HD Pro Webcam C920 at usb-...
+/// ```
+/// The bracket contains the short name that cpal reports; the text
+/// after the colon on that same line is the description we want. The
+/// next indented line is a longer location string we ignore.
+fn load_alsa_card_descriptions() -> std::collections::HashMap<String, String> {
+    use std::collections::HashMap;
+    let mut map = HashMap::new();
+    #[cfg(target_os = "linux")]
+    {
+        let Ok(contents) = std::fs::read_to_string("/proc/asound/cards") else {
+            return map;
+        };
+        for line in contents.lines() {
+            // Header lines start with an optional leading space plus a
+            // digit (the card ID, right-aligned to 2 chars for readable
+            // formatting). Continuation lines are indented beyond that.
+            let trimmed = line.trim_start();
+            if !trimmed.chars().next().map(|c| c.is_ascii_digit()).unwrap_or(false) {
+                continue;
+            }
+            let Some(open) = trimmed.find('[') else { continue };
+            let Some(close) = trimmed[open..].find(']') else { continue };
+            let short_name = trimmed[open + 1..open + close].trim().to_string();
+            if short_name.is_empty() {
+                continue;
+            }
+            let after_bracket = &trimmed[open + close + 1..];
+            let Some(colon) = after_bracket.find(':') else { continue };
+            // Format: "USB-Audio - Blue Microphones"
+            // We keep everything after the " - " if present, otherwise
+            // the whole post-colon fragment.
+            let raw = after_bracket[colon + 1..].trim();
+            let description = raw
+                .split(" - ")
+                .nth(1)
+                .map(|s| s.trim().to_string())
+                .unwrap_or_else(|| raw.to_string());
+            if !description.is_empty() {
+                map.insert(short_name, description);
+            }
+        }
+    }
+    map
+}
+
 /// Open the given device and validate it produces non-silent audio.
 /// If `require_audio` is false, accept any data (used for monitor fallback).
 fn open_and_validate(