refactor: voice resolution on ConversionRequest, PipelinePool without job param

- Added speakers field to ConversionRequest
- Rewrote collect_required_voice_ids(), initialize_voice_cache(),
  job_voice_fallback(), chapter_voice_spec(), chunk_voice_spec()
  to accept ConversionRequest instead of job
- PipelinePool.get() now takes request= instead of job=
- Updated all tests to use ConversionRequest interface
- 1493 tests passing

abogen/application/conversion_request.py

@@ -95,6 +95,9 @@ class ConversionRequest:
     # --- Metadata ---
     metadata_tags: Dict[str, Any] = field(default_factory=dict)
 
+    # --- Voice profiles (loaded by UI, used by app for voice resolution) ---
+    speakers: Dict[str, Any] = field(default_factory=dict)
+
     # --- Artifacts ---
     cover_image_path: Optional[Path] = None
     cover_image_mime: Optional[str] = None

abogen/domain/pipeline_factory.py

@@ -95,7 +95,8 @@ class PipelinePool:
         language: str,
         use_gpu: bool,
         *,
-        job: Any = None,
+        request: Any = None,
+        events: Any = None,
     ) -> Any:
         """Get or create a cached pipeline for the given provider.
 
@@ -103,7 +104,8 @@ class PipelinePool:
             provider: TTS provider name ("kokoro" or "supertonic").
             language: Language code (for kokoro).
             use_gpu: Whether GPU acceleration is requested.
-            job: Optional job object for voice cache initialization.
+            request: ConversionRequest for voice cache initialization.
+            events: ConversionEvents for logging during cache init.
         """
         provider = str(provider or "kokoro").strip().lower() or "kokoro"
         if not is_plugin_registered(provider):
@@ -116,8 +118,8 @@ class PipelinePool:
         pipeline = create_pipeline_for_job(provider, language, use_gpu)
         self._pipelines[provider] = pipeline
 
-        if provider == "kokoro" and not self._voice_cache_initialized and job is not None:
-            initialize_voice_cache(job)
+        if provider == "kokoro" and not self._voice_cache_initialized and request is not None:
+            initialize_voice_cache(request, events=events)
             self._voice_cache_initialized = True
 
         return pipeline

abogen/domain/voice_resolution.py

@@ -2,6 +2,9 @@
 
 Functions for resolving voice specifications, collecting required voice IDs,
 and determining the voice to use for chapters and chunks.
+
+All functions accept ConversionRequest (the app-layer contract) instead of
+UI-specific objects. This keeps the domain layer UI-agnostic.
 """
 
 from __future__ import annotations
@@ -29,12 +32,28 @@ def spec_to_voice_ids(spec: Any) -> Set[str]:
     return set()
 
 
-def job_voice_fallback(job: Any) -> str:
-    base = str(getattr(job, "voice", "") or "").strip()
+def _get_chapter_overrides(request: Any) -> list:
+    """Extract chapter overrides from ConversionRequest."""
+    cc = getattr(request, "chapter_chunk", None)
+    if cc is not None:
+        return getattr(cc, "chapter_overrides", []) or []
+    return []
+
+
+def _get_chunks(request: Any) -> list:
+    """Extract chunks from ConversionRequest."""
+    cc = getattr(request, "chapter_chunk", None)
+    if cc is not None:
+        return getattr(cc, "chunks", []) or []
+    return []
+
+
+def job_voice_fallback(request: Any) -> str:
+    base = str(getattr(request, "voice", "") or "").strip()
     if base and base != "__custom_mix":
         return base
 
-    speakers = getattr(job, "speakers", None)
+    speakers = getattr(request, "speakers", None)
     if isinstance(speakers, dict):
         narrator = speakers.get("narrator")
         if isinstance(narrator, dict):
@@ -52,7 +71,7 @@ def job_voice_fallback(job: Any) -> str:
                 if candidate and candidate != "__custom_mix":
                     return candidate
 
-    for chapter in getattr(job, "chapters", []) or []:
+    for chapter in _get_chapter_overrides(request):
         if not isinstance(chapter, dict):
             continue
         for key in ("resolved_voice", "voice_formula", "voice"):
@@ -63,24 +82,24 @@ def job_voice_fallback(job: Any) -> str:
     return ""
 
 
-def collect_required_voice_ids(job: Any) -> Set[str]:
+def collect_required_voice_ids(request: Any) -> Set[str]:
     voices: Set[str] = set()
-    voices.update(spec_to_voice_ids(job.voice))
-    voices.update(spec_to_voice_ids(job_voice_fallback(job)))
+    voices.update(spec_to_voice_ids(request.voice))
+    voices.update(spec_to_voice_ids(job_voice_fallback(request)))
 
-    for chapter in getattr(job, "chapters", []) or []:
+    for chapter in _get_chapter_overrides(request):
         if not isinstance(chapter, dict):
             continue
         for key in ("resolved_voice", "voice_formula", "voice"):
             voices.update(spec_to_voice_ids(chapter.get(key)))
 
-    for chunk in getattr(job, "chunks", []) or []:
+    for chunk in _get_chunks(request):
         if not isinstance(chunk, dict):
             continue
         for key in ("resolved_voice", "voice_formula", "voice"):
             voices.update(spec_to_voice_ids(chunk.get(key)))
 
-    speakers = getattr(job, "speakers", {})
+    speakers = getattr(request, "speakers", {})
     if isinstance(speakers, dict):
         for payload in speakers.values() or []:
             if not isinstance(payload, dict):
@@ -92,30 +111,38 @@ def collect_required_voice_ids(job: Any) -> Set[str]:
     return voices
 
 
-def initialize_voice_cache(job: Any) -> None:
+def initialize_voice_cache(request: Any, events: Any = None) -> None:
+    """Initialize voice cache by downloading required voice assets.
+
+    Args:
+        request: ConversionRequest with voice/chapter/chunk/speaker info.
+        events: ConversionEvents for logging (optional, for backward compat).
+    """
+    log = (lambda msg, level="info": events.log(msg, level=level)) if events else (lambda msg, level="info": None)
+
     try:
-        targets = collect_required_voice_ids(job)
+        targets = collect_required_voice_ids(request)
         downloaded, errors = ensure_voice_assets(
             targets,
-            on_progress=lambda message: job.add_log(message, level="debug"),
+            on_progress=lambda message: log(message, level="debug"),
         )
     except RuntimeError as exc:
-        job.add_log(f"Voice cache unavailable: {exc}", level="warning")
+        log(f"Voice cache unavailable: {exc}", level="warning")
         return
 
     if downloaded:
-        job.add_log(
+        log(
             f"Cached {len(downloaded)} voice asset{'s' if len(downloaded) != 1 else ''} locally.",
             level="info",
         )
 
     for voice_id, error in errors.items():
-        job.add_log(f"Failed to cache voice '{voice_id}': {error}", level="warning")
+        log(f"Failed to cache voice '{voice_id}': {error}", level="warning")
 
 
-def chapter_voice_spec(job: Any, override: Optional[Dict[str, Any]]) -> str:
+def chapter_voice_spec(request: Any, override: Optional[Dict[str, Any]]) -> str:
     if not override:
-        return job_voice_fallback(job)
+        return job_voice_fallback(request)
 
     resolved = str(override.get("resolved_voice", "")).strip()
     if resolved:
@@ -129,17 +156,17 @@ def chapter_voice_spec(job: Any, override: Optional[Dict[str, Any]]) -> str:
     if voice:
         return voice
 
-    return job_voice_fallback(job)
+    return job_voice_fallback(request)
 
 
-def chunk_voice_spec(job: Any, chunk: Dict[str, Any], fallback: str) -> str:
+def chunk_voice_spec(request: Any, chunk: Dict[str, Any], fallback: str) -> str:
     for key in ("resolved_voice", "voice_formula", "voice"):
         value = chunk.get(key)
         if value:
             return str(value)
 
     speaker_id = chunk.get("speaker_id")
-    speakers = getattr(job, "speakers", None)
+    speakers = getattr(request, "speakers", None)
     if isinstance(speakers, dict) and speaker_id in speakers:
         speaker_entry = speakers.get(speaker_id) or {}
         if isinstance(speaker_entry, dict):
@@ -163,7 +190,7 @@ def chunk_voice_spec(job: Any, chunk: Dict[str, Any], fallback: str) -> str:
 
     if fallback:
         return fallback
-    return job_voice_fallback(job)
+    return job_voice_fallback(request)
 
 
 def resolve_fallback_voice_spec(