Returns a newline-separated list of file paths relative to the vault root.
Use these exact paths with get_file_content() to read file contents.
Excludes system directories like .obsidian.

Example return format:
notes/meeting-notes.md
projects/project-alpha.md
daily/2024-01-15.md

Args:
    file_path: The relative file path from the vault root. Use the exact path
              format returned by list_files() or find_files().
              Examples: 'notes/meeting-notes.md', 'daily/2024-01-15.md'
              This parameter is REQUIRED - you must specify which file to read.

Returns:
    The full text content of the file, or an error message if the file
    cannot be read or doesn't exist.

Note: Only reads text files. Binary files will return an encoding error.

Args:
    query: Search term to match against file names (case-insensitive).
           Can be a partial filename, extension, or keyword.
           Examples: 'meeting', '.md', 'project-alpha'

Returns:
    List of relative file paths that match the query.
    Use these paths with get_file_content() to read the files.
    Returns message if no matches found.

Note: Searches only file names/paths, not file contents. Use find_in_all_file_content()
      to search within file contents.

Args:
    query: Text to search for within file contents (case-insensitive).
           Can be words, phrases, or partial text.
           Examples: 'meeting notes', 'project deadline', 'TODO'

Returns:
    Newline-separated list of file paths that contain the query text.
    Only returns the file paths, not the matching content excerpts.
    Use get_file_content() on returned paths to read the full files.
    Returns message if no matches found.

Note: Searches the full text content of all readable files. Skips binary files.
      For filename searches, use find_files() instead.