fix: resolve nodriver RemoteObject conversion bug (#651)

## ℹ️ Description
*Fixes the nodriver 0.47.0 RemoteObject conversion bug that was causing
KeyError and TypeError when accessing BelenConf dimensions.*

- Link to the related issue(s): Issue #650
- The bot was crashing when downloading ads because nodriver 0.47.0 was
returning JavaScript objects as lists of [key, value] pairs instead of
proper Python dictionaries, causing BelenConf dimensions to be
inaccessible.

## 📋 Changes Summary

- **Fixed nodriver RemoteObject conversion bug** in
`web_scraping_mixin.py`:
- Added detection logic for list-of-pairs format in `web_execute` method
- Enhanced `_convert_remote_object_dict` to recursively convert nested
structures
  - Now properly converts JavaScript objects to Python dictionaries
- **Bot functionality fully restored** - can now download ads with
subcategories and special attributes

### ⚙️ Type of Change
- [x] 🐞 Bug fix (non-breaking change which fixes an issue)
- [ ] ✨ New feature (adds new functionality without breaking existing
usage)
- [ ] 💥 Breaking change (changes that might break existing user setups,
scripts, or configurations)

## ✅ Checklist
- [x] I have reviewed my changes to ensure they meet the project's
standards.
- [x] I have tested my changes and ensured that all tests pass (`pdm run
test`).
- [x] I have formatted the code (`pdm run format`).
- [x] I have verified that linting passes (`pdm run lint`).
- [x] I have updated documentation where necessary.

By submitting this pull request, I confirm that you can use, modify,
copy, and redistribute this contribution, under the terms of your
choice.

src/kleinanzeigen_bot/utils/web_scraping_mixin.py

@@ -44,6 +44,7 @@ METACHAR_ESCAPER:Final[dict[int, str]] = str.maketrans({ch: f"\\{ch}" for ch in
 
 # Constants for RemoteObject handling
 _REMOTE_OBJECT_TYPE_VALUE_PAIR_SIZE:Final[int] = 2
+_KEY_VALUE_PAIR_SIZE:Final[int] = 2
 
 
 def _is_admin() -> bool:
@@ -579,6 +580,15 @@ class WebScrapingMixin:
         if hasattr(result, "deep_serialized_value"):
             return self._convert_remote_object_result(result)
 
+        # Fix for nodriver 0.47+ bug: convert list-of-pairs back to dict
+        if isinstance(result, list) and all(isinstance(item, list) and len(item) == _KEY_VALUE_PAIR_SIZE for item in result):
+            # This looks like a list of [key, value] pairs that should be a dict
+            converted_dict = {}
+            for key, value in result:
+                # Recursively convert nested structures
+                converted_dict[key] = self._convert_remote_object_dict(value)
+            return converted_dict
+
         return result
 
     def _convert_remote_object_result(self, result:Any) -> Any:
@@ -601,7 +611,11 @@ class WebScrapingMixin:
                 # Convert list of [key, value] pairs to dict, handling nested RemoteObjects
                 converted_dict = {}
                 for key, value in serialized_data:
-                    converted_dict[key] = self._convert_remote_object_dict(value)
+                    # Handle the case where value is a RemoteObject with type/value structure
+                    if isinstance(value, dict) and "type" in value and "value" in value:
+                        converted_dict[key] = self._convert_remote_object_dict(value)
+                    else:
+                        converted_dict[key] = self._convert_remote_object_dict(value)
                 return converted_dict
 
             if isinstance(serialized_data, dict):
@@ -623,10 +637,24 @@ class WebScrapingMixin:
         if isinstance(data, dict):
             # Check if this is a RemoteObject value structure
             if "type" in data and "value" in data and len(data) == _REMOTE_OBJECT_TYPE_VALUE_PAIR_SIZE:
-                return data["value"]
+                # Extract the actual value and recursively convert it
+                value = data["value"]
+                if isinstance(value, list) and all(isinstance(item, list) and len(item) == _KEY_VALUE_PAIR_SIZE for item in value):
+                    # This is a list of [key, value] pairs that should be a dict
+                    converted_dict = {}
+                    for key, val in value:
+                        converted_dict[key] = self._convert_remote_object_dict(val)
+                    return converted_dict
+                return self._convert_remote_object_dict(value)
             # Recursively convert nested dicts
             return {key: self._convert_remote_object_dict(value) for key, value in data.items()}
         if isinstance(data, list):
+            # Check if this is a list of [key, value] pairs that should be a dict
+            if all(isinstance(item, list) and len(item) == _KEY_VALUE_PAIR_SIZE for item in data):
+                converted_dict = {}
+                for key, value in data:
+                    converted_dict[key] = self._convert_remote_object_dict(value)
+                return converted_dict
             # Recursively convert lists
             return [self._convert_remote_object_dict(item) for item in data]
         # Return primitive values as-is