feat(whisper): add Distil-Whisper Small and Large v3 as first-class models

Two new registry entries (crates/core/src/model_registry.rs):
- whisper-distil-small-en — 336 MB, ~6× faster than whisper-small-en
- whisper-distil-large-v3 — 1.55 GB, near large-v3 accuracy at medium size

Both are whisper.cpp-compatible GGML binaries hosted on HF by the
distil-whisper org; no runtime change, just wider model choice. English-only
by design (matches upstream Distil-Whisper).

The Settings model picker widens to six options — Tiny, Base, Small,
Distil-S, Medium, Distil-L — ordered roughly by accuracy. Download/load
commands now take the resolved model id (whisper-distil-*) instead of the
lowercased label, so the frontend owns the label↔id mapping.

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

crates/core/src/model_registry.rs

@@ -150,6 +150,23 @@ static ALL_MODELS: LazyLock<Vec<ModelEntry>> = LazyLock::new(|| {
             }],
             description: "Accuracy-first English transcription",
         },
+        ModelEntry {
+            id: ModelId::new("whisper-distil-small-en"),
+            engine: Engine::Whisper,
+            display_name: "Distil-Whisper Small (English)",
+            disk_size: Megabytes(336),
+            ram_required: Megabytes(900),
+            speed_tier: SpeedTier::Fast,
+            accuracy_tier: AccuracyTier::Great,
+            languages: LanguageSupport::EnglishOnly,
+            files: vec![ModelFile {
+                filename: "ggml-distil-small.en.bin",
+                url: "https://huggingface.co/distil-whisper/distil-small.en/resolve/main/ggml-distil-small.en.bin",
+                size: Megabytes(336),
+                sha256: None,
+            }],
+            description: "Small accuracy, ~6\u{00d7} faster — distilled variant",
+        },
         ModelEntry {
             id: ModelId::new("whisper-medium-en"),
             engine: Engine::Whisper,
@@ -167,6 +184,23 @@ static ALL_MODELS: LazyLock<Vec<ModelEntry>> = LazyLock::new(|| {
             }],
             description: "Best Whisper accuracy — needs 4+ GB RAM",
         },
+        ModelEntry {
+            id: ModelId::new("whisper-distil-large-v3"),
+            engine: Engine::Whisper,
+            display_name: "Distil-Whisper Large v3 (English)",
+            disk_size: Megabytes(1550),
+            ram_required: Megabytes(2800),
+            speed_tier: SpeedTier::Moderate,
+            accuracy_tier: AccuracyTier::Excellent,
+            languages: LanguageSupport::EnglishOnly,
+            files: vec![ModelFile {
+                filename: "ggml-distil-large-v3.bin",
+                url: "https://huggingface.co/distil-whisper/distil-large-v3-ggml/resolve/main/ggml-distil-large-v3.bin",
+                size: Megabytes(1550),
+                sha256: None,
+            }],
+            description: "Near large-v3 accuracy at ~6\u{00d7} the speed",
+        },
     ]
 });
 

src-tauri/src/commands/models.rs

@@ -15,7 +15,11 @@ fn whisper_model_id(size: &str) -> ModelId {
         "tiny" => ModelId::new("whisper-tiny-en"),
         "base" => ModelId::new("whisper-base-en"),
         "small" => ModelId::new("whisper-small-en"),
+        "distil-small" | "distilsmall" => ModelId::new("whisper-distil-small-en"),
         "medium" => ModelId::new("whisper-medium-en"),
+        "distil-large" | "distil-large-v3" | "distillarge" => {
+            ModelId::new("whisper-distil-large-v3")
+        }
         other => ModelId::new(other),
     }
 }
@@ -297,7 +301,9 @@ pub fn list_models() -> Result<Vec<String>, String> {
             "whisper-tiny-en" => "Tiny".to_string(),
             "whisper-base-en" => "Base".to_string(),
             "whisper-small-en" => "Small".to_string(),
+            "whisper-distil-small-en" => "Distil-S".to_string(),
             "whisper-medium-en" => "Medium".to_string(),
+            "whisper-distil-large-v3" => "Distil-L".to_string(),
             other => other.to_string(),
         })
         .collect())

src/lib/pages/SettingsPage.svelte

@@ -337,7 +337,9 @@
       Tiny: "whisper-tiny-en",
       Base: "whisper-base-en",
       Small: "whisper-small-en",
+      "Distil-S": "whisper-distil-small-en",
       Medium: "whisper-medium-en",
+      "Distil-L": "whisper-distil-large-v3",
     };
     return map[size] || "whisper-base-en";
   }
@@ -614,7 +616,7 @@
   }
 
   async function loadSelectedModel() {
-    const size = settings.modelSize.toLowerCase();
+    const size = whisperModelId(settings.modelSize);
     engineStatus = "Loading...";
     engineOk = false;
     try {
@@ -650,7 +652,9 @@
     Tiny: "~75MB · fastest, lower accuracy",
     Base: "~150MB · balanced for most use",
     Small: "~500MB · noticeably more accurate",
-    Medium: "~1.5GB · best quality, slower",
+    "Distil-S": "~336MB · small-level accuracy at ~6× the speed",
+    Medium: "~1.5GB · best Whisper accuracy, slower",
+    "Distil-L": "~1.55GB · near-large accuracy at ~6× the speed",
   };
 
   async function downloadParakeet() {
@@ -1004,7 +1008,7 @@
             {#if settings.engine === "whisper"}
               <div class="mb-6">
                 <p class="text-[10px] font-medium text-text-tertiary uppercase tracking-wider mb-2">Whisper Model</p>
-                <SegmentedButton options={["Tiny", "Base", "Small", "Medium"]} bind:value={settings.modelSize} />
+                <SegmentedButton options={["Tiny", "Base", "Small", "Distil-S", "Medium", "Distil-L"]} bind:value={settings.modelSize} />
                 <p class="text-[11px] text-text-tertiary mt-2">{modelDescriptions[settings.modelSize]}</p>
 
                 <div class="flex items-center gap-2 mt-3">
@@ -1022,12 +1026,12 @@
                       class="text-[11px] text-text-tertiary hover:text-accent"
                       onclick={loadSelectedModel}
                     >Load model</button>
-                  {:else if downloadingModel === settings.modelSize.toLowerCase()}
+                  {:else if downloadingModel === whisperModelId(settings.modelSize)}
                     <span class="text-[11px] text-warning">{downloadProgress}% downloading...</span>
                   {:else}
                     <button
                       class="text-[11px] text-accent hover:text-accent-hover"
-                      onclick={() => downloadModel(settings.modelSize.toLowerCase())}
+                      onclick={() => downloadModel(whisperModelId(settings.modelSize))}
                     >Download {settings.modelSize}</button>
                   {/if}
                 </div>

src/lib/types/app.ts

@@ -3,7 +3,13 @@ export type FontFamily = "lexend" | "atkinson" | "opendyslexic";
 export type ReduceMotion = "system" | "on" | "off";
 export type RecordingEngine = "whisper" | "parakeet";
 export type FormatMode = "Raw" | "Clean" | "Smart";
-export type WhisperModelSize = "Tiny" | "Base" | "Small" | "Medium";
+export type WhisperModelSize =
+  | "Tiny"
+  | "Base"
+  | "Small"
+  | "Distil-S"
+  | "Medium"
+  | "Distil-L";
 export type AiTier = "off" | "cleanup" | "tasks";
 export type LlmModelIdStr = "qwen3_1_7b" | "qwen3_4b_instruct_2507" | "qwen3_14b";
 export type TaskBucket = "inbox" | "today" | "soon" | "later";