Fix indexing and query parsing issues

[Alidra]

Summary:

• Fix parsing to preserve trailing characters after query
• Restore notation support by correcting required file requiring in cli/lambdapi.ml
• Add position info to query command error messages
• Prevent websearch server from crashing in case of syntax errors
• Restore the feature of streaming the search results in command line
• Use uniform types for query formatting functions and remove dual syntax-tree/string acceptance

Details:

• This branch implements several minor fixes after Improvements and new features for indexing #1290 , focused on search indexing and query handling. It ensures query parsing is handled in the right phase, improves CLI error reporting, and prevents incorrect search results when syntax errors occur.

[Alidra]

@sacerdot @fblanqui I believe this PR is ready for merge.
There is still a problem with the parser because the list function does not behave expected in case of erroneous trailing tokens after the one expected with prefix but this problem is beyond the current changes and I propose to fix it in a dedicated PR

[fblanqui]

Thanks for your PR. But there are many changes that are not true changes, just reindentation. Could you please minimize the diff. Ill review it once it will be minimized.

[fblanqui]

Thank you @Alidra !