build: eliminate duplicate HTTP stack by standardizing on async (tokio/reqwest)

Unified hf-hub feature declarations across all crates to use only the async API
(tokio/reqwest), removing the sync API (ureq) from the dependency tree entirely.

Changes:
- whisperforge-core: switch hf-hub from ureq→tokio feature; add minimal tokio
  runtime (rt feature only) embedded in ensure_silero_model()
- whisperforge: explicit default-features=false on hf-hub to prevent ureq
  re-entry via feature unification
- vad_silero.rs: refactor ensure_silero_model() to use async API internally
  while preserving synchronous public signature (block_on pattern)

Result: ureq@3.3.0 eliminated, single HTTP client (reqwest) in binary.
Dependency reduction: 715 → 681 nodes (-34, -4.8%).
No breaking API changes; tokio runtime created locally per download (negligible cost).

Author: bevsxyz

Cargo.lock

@@ -34,7 +34,8 @@ cpal = { workspace = true }
 ringbuf = { workspace = true }
 tracing = { workspace = true }
 ort = { workspace = true }
-hf-hub = { version = "0.5", default-features = false, features = ["ureq"] }
+hf-hub = { version = "0.5", default-features = false, features = ["tokio"] }
+tokio = { version = "1", default-features = false, features = ["rt"] }
 hound = "3.5"
 
 [features]

whisperforge-core/Cargo.toml

@@ -1,5 +1,5 @@
 use anyhow::{Context, Result};
-use hf_hub::{Repo, RepoType, api::sync::ApiBuilder};
+use hf_hub::{Repo, RepoType, api::tokio::ApiBuilder};
 use ort::{session::Session, value::TensorRef};
 use std::path::{Path, PathBuf};
 
@@ -99,17 +99,26 @@ pub fn ensure_silero_model(models_dir: &Path) -> Result<PathBuf> {
     std::fs::create_dir_all(models_dir)
         .with_context(|| format!("create models dir {}", models_dir.display()))?;
 
+    let rt = tokio::runtime::Builder::new_current_thread()
+        .enable_all()
+        .build()
+        .context("creating tokio runtime")?;
+    rt.block_on(download_silero_model(models_dir, &target))
+}
+
+async fn download_silero_model(_models_dir: &Path, target: &Path) -> Result<PathBuf> {
     let api = ApiBuilder::from_env()
         .build()
         .context("HuggingFace API init")?;
     let cached = api
         .repo(Repo::new(SILERO_REPO.to_string(), RepoType::Model))
         .get(SILERO_HF_FILE)
+        .await
         .with_context(|| format!("download {SILERO_HF_FILE} from {SILERO_REPO}"))?;
 
-    std::fs::copy(&cached, &target).with_context(|| format!("copy to {}", target.display()))?;
+    std::fs::copy(&cached, target).with_context(|| format!("copy to {}", target.display()))?;
 
-    Ok(target)
+    Ok(target.to_path_buf())
 }
 
 #[cfg(test)]

whisperforge-core/src/vad_silero.rs

@@ -58,7 +58,7 @@ burn-wgpu = { version = "0.21.0", optional = true }
 burn-cuda = { version = "0.21.0", optional = true }
 # Model conversion (`wforge convert`) deps.
 safetensors = "0.7"
-hf-hub = { version = "0.5", features = ["tokio"] }
+hf-hub = { version = "0.5", default-features = false, features = ["tokio"] }
 tokio = { version = "1.36.0", features = ["rt-multi-thread", "rt", "signal", "macros"] }
 half = "2.3.1"
 hound = "3.5"