Update pylint to v4

[chvp]

The two work-arounds for pylint issues in our codebase could be removed:

• The linting of code importing re and using pandas dataframes now works
• The os.devnull workaround also isn't required anymore for getting linting results.

Closes #997

[Copilot]

Pull request overview

Updates the Papyros Python worker’s linting stack to support Pylint v4, including updating the custom AST checker implementation and adjusting runtime/config workarounds previously needed in Pyodide.

Changes:

• Bump packaged dependency from pylint<3.0.0 to pylint>=4,<5.
• Update the custom pylint_ast_checker plugin to newer Pylint/Astroid APIs (only_required_for_messages, visit_call, astroid.nodes).
• Simplify lint execution by removing prior Pyodide-specific workarounds (AstroidManager patch and os.devnull override) and updating disabled message IDs in the rcfile.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/backend/workers/python/papyros/pylint_config.rc	Updates disabled message IDs to match newer Pylint docstring checks and adjusts the suppression list.
src/backend/workers/python/papyros/pylint_ast_checker.py	Migrates custom checker implementation to updated Pylint/Astroid APIs and node classes.
src/backend/workers/python/papyros/papyros.py	Removes the os.devnull linting workaround in the Pyodide runner’s lint() method.
src/backend/workers/python/papyros/linting.py	Removes the AstroidManager module-resolution short-circuit patch previously used to avoid hangs in Pyodide.
src/backend/workers/python/build_package.py	Updates the packaged dependency constraint to pylint>=4,<5.

Comments suppressed due to low confidence (1)

src/backend/workers/python/papyros/linting.py:18

• This change removes the earlier AstroidManager patch that short-circuited module resolution to avoid indefinite hangs in the single-threaded Pyodide/WASM environment. There’s no replacement safeguard here (e.g., a timeout, a version-guarded patch, or a test proving the hang is fixed in the new pylint/astroid versions), so a regression could stall the worker during linting. Please either restore a guarded workaround or add a regression test/clear evidence that pylint>=4 no longer triggers this hang in Pyodide.

from pylint.lint import Run
from pylint.reporters.text import TextReporter


PYLINT_RC_FILE = os.path.abspath("/tmp/papyros/pylint_config.rc")
PYLINT_PLUGINS = "pylint_ast_checker"

def lint(code):
    # Use temporary file to prevent Astroid cache from running into issues
    with NamedTemporaryFile() as tmpf:
        tmpf.write(bytes(code, encoding="utf-8"))
        tmpf.seek(0)

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