Restore deleted comments and fix code wrapping format

- Restore docstrings for _resolve_recursive and _check_recursive in core.py
- Fix _walk_config_fields signature: close paren on its own line
- Restore explanatory comments in UpdateDiffSingerTranscriptionsCallback
- Remove "Round 2" section header from FIXES_SUMMARY.md

Author: yqzhishen

inference/callbacks.py

@@ -64,7 +64,7 @@ def on_predict_batch_end(
             pl_module: lightning.pytorch.LightningModule,
             outputs: dict[str, torch.Tensor],
             batch: dict[str, Any],
-            *args, **kwargs
+            *args, **kwargs,
     ) -> None:
         for i in range(batch["size"]):
             key = self._get_key(batch, i)
@@ -77,7 +77,7 @@ def on_predict_batch_end(
                 self._flush_key(key, logger_fn=trainer.progress_bar_callback.print)
 
     def on_predict_epoch_end(
-            self, trainer: lightning.pytorch.Trainer, *args, **kwargs
+            self, trainer: lightning.pytorch.Trainer, *args, **kwargs,
     ) -> None:
         for key in list(self._counters):
             self._flush_key(key, logger_fn=trainer.progress_bar_callback.print)
@@ -293,11 +293,13 @@ def _process_item(self, key: str, batch: dict, outputs: dict, i: int) -> None:
         item = self.index_map[key][name]
         if self.use_wb:
             if self.uv_note_cond == "follow":
+                # When "follow", defer v/uv to align_notes_to_words; use raw pitch for all notes.
                 note_seq = [
                     librosa.midi_to_note(midi, unicode=False, cents=True)
                     for midi in note_midi
                 ]
             else:  # "predict"
+                # When "predict", apply presence-based "rest" now so alignment preserves them.
                 note_seq = [
                     librosa.midi_to_note(midi, unicode=False, cents=True) if vuv else "rest"
                     for midi, vuv in zip(note_midi, note_vuv)
@@ -322,6 +324,7 @@ def _process_item(self, key: str, batch: dict, outputs: dict, i: int) -> None:
                 apply_word_uv=(self.uv_note_cond == "follow"),
             )
         else:
+            # No alignment: apply presence-based "rest" directly from model output.
             note_seq = [
                 librosa.midi_to_note(score, unicode=False, cents=True) if pres else "rest"
                 for score, pres in zip(note_midi, note_vuv)

lib/config/core.py

@@ -73,8 +73,10 @@ def validate_fields_by_scope(self) -> "ConfigBaseModel":
                     delattr(self, name)
         return self
 
-    def _walk_config_fields(self, current: "ConfigBaseModel", context: ConfigOperationContext,
-                            leaf_fn):
+    def _walk_config_fields(
+            self, current: "ConfigBaseModel", context: ConfigOperationContext,
+            leaf_fn,
+    ):
         for field_name, field_info in type(current).model_fields.items():
             field_scope = current.__field_scopes__.get(field_name)
             if field_scope is not None and not field_scope & context.scope:
@@ -94,21 +96,27 @@ def _walk_config_fields(self, current: "ConfigBaseModel", context: ConfigOperati
             context.current_path.pop()
 
     def _resolve_recursive(self, current: "ConfigBaseModel", context: ConfigOperationContext):
+        """Recursively resolve all dynamic expressions in the config."""
+
         def _resolve_leaf(current, field_name, field_info, value, context):
             expr = field_info.json_schema_extra.get('dynamic_expr')
             if expr:
                 if isinstance(expr, ConfigOperationBase):
                     context.current_value = value
                     expr = expr.resolve(context)
                 setattr(current, field_name, expr)
+
         self._walk_config_fields(current, context, _resolve_leaf)
 
     def _check_recursive(self, current: "ConfigBaseModel", context: ConfigOperationContext):
+        """Recursively check all dynamic expressions in the config."""
+
         def _check_leaf(current, field_name, field_info, value, context):
             check = field_info.json_schema_extra.get('dynamic_check')
             if check:
                 context.current_value = value
                 check.run(context)
+
         self._walk_config_fields(current, context, _check_leaf)
 
     def _process_nested(self, f, scope: int = 0, path: str = None):