[FIX] graceful error when failing to load invalid yml

[Remi-Gau]

• closes ungracefull error when loading schema with yaml syntax error #2008

[Remi-Gau]

The error at least now mentions in which file the error is.

2024-12-16 11:28:13,235 [    INFO] No schema path specified, defaulting to the bundled schema, `/home/remi/github/bids/website/env/lib/python3.12/site-packages/bidsschematools/data/schema`.
Traceback (most recent call last):
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/bidsschematools/types/namespace.py", line 279, in _read_yaml_dir
    mapping[subpath.stem] = yaml.safe_load(subpath.read_text())
                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/yaml/__init__.py", line 125, in safe_load
    return load(stream, SafeLoader)
           ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/yaml/__init__.py", line 81, in load
    return loader.get_single_data()
           ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/yaml/constructor.py", line 49, in get_single_data
    node = self.get_single_node()
           ^^^^^^^^^^^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/yaml/composer.py", line 36, in get_single_node
    document = self.compose_document()
               ^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/yaml/composer.py", line 55, in compose_document
    node = self.compose_node(None, None)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/yaml/composer.py", line 84, in compose_node
    node = self.compose_mapping_node(anchor)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/yaml/composer.py", line 133, in compose_mapping_node
    item_value = self.compose_node(node, item_key)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/yaml/composer.py", line 84, in compose_node
    node = self.compose_mapping_node(anchor)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/yaml/composer.py", line 127, in compose_mapping_node
    while not self.check_event(MappingEndEvent):
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/yaml/parser.py", line 98, in check_event
    self.current_event = self.state()
                         ^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/yaml/parser.py", line 428, in parse_block_mapping_key
    if self.check_token(KeyToken):
       ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/yaml/scanner.py", line 116, in check_token
    self.fetch_more_tokens()
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/yaml/scanner.py", line 223, in fetch_more_tokens
    return self.fetch_value()
           ^^^^^^^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/yaml/scanner.py", line 577, in fetch_value
    raise ScannerError(None, None,
yaml.scanner.ScannerError: mapping values are not allowed here
  in "<unicode string>", line 8, column 15:
      display_name: Acquisition
                  ^

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/bidsschematools/types/namespace.py", line 277, in _read_yaml_dir
    mapping[subpath.name] = _read_yaml_dir(subpath)
                            ^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/bidsschematools/types/namespace.py", line 281, in _read_yaml_dir
    raise ValueError(f"There was an error reading the file: {subpath}") from e
ValueError: There was an error reading the file: /home/remi/github/bids/website/env/lib/python3.12/site-packages/bidsschematools/data/schema/objects/entities.yaml

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/home/remi/github/bids/specification/tmp.py", line 2, in <module>
    schema_obj = schema.load_schema()
                 ^^^^^^^^^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/bidsschematools/schema.py", line 203, in load_schema
    schema = Namespace.from_directory(schema_path)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/bidsschematools/types/namespace.py", line 261, in from_directory
    return cls.build(_read_yaml_dir(Path(path)))
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/remi/github/bids/website/env/lib/python3.12/site-packages/bidsschematools/types/namespace.py", line 281, in _read_yaml_dir
    raise ValueError(f"There was an error reading the file: {subpath}") from e
ValueError: There was an error reading the file: /home/remi/github/bids/website/env/lib/python3.12/site-packages/bidsschematools/data/schema/objects

[Remi-Gau]

adding this extra check because the wesbite would still build but with broken pages which is not something we want