Refactor for libmamba v2

[jaimergp]

Description

Adds compatibility for libmamba v2, which enables a few refactors (see below). Supersedes conda/conda#414.

• Will close conda with libmamba solver does not work in offline mode #522

Progress:

• Refactor index helpers
• Refactor repoquery
• Refactor solver
• Refactor conflict reports
• Pass all tests
• Polish and clean up

Checklist - did you ...

• Add a file to the news directory (using the template) for the next release's release notes?
• Add / update necessary tests?
• Add / update outdated documentation?

Summary of changes

• Deprecate CONDA_LIBMAMBA_SOLVER_NO_CHANNELS_FROM_INSTALLED. No longer needed with v2. Closes pip-integration: --dry-run still installs with pip conda#411
• Added typing for all methods and functions
• Added time_recorder decorator for metadata collection and solving loop
• Removed state.BaseIndexHelper. We just have our index.IndexHelper now
• The libmamba v1 pool (collection of repos, where a repo represents a loaded repodata.json) is now a database of RepoInfo objects.
• Do use current_repodata.json if explicitly set in CLI
• Move to Ruff for pre-commit linting & formatting
• Logging from libsolv has a HUGE overhead now because it goes from C to C++ to Python to logging to stdout instead of C -> stdout. To enable libsolv verbosity, an extra environment variable CONDA_LIBMAMBA_SOLVER_DEBUG_LIBSOLV is required.
• allow_uninstall was previously set to false (only true for conda remove), and we set it up for individual solver jobs involving updates or conflicts. With v2, we have individual control over what to "Keep" instead of drop. This required marking important updates as keepers instead. Otherwise they would be uninstalled.
• Other changes in the test suite discussed in Amend test suite for compatibility with libmamba v2 conda#13784

[jaimergp]

pre-commit.ci autofix

[jaimergp]

@conda/conda-libmamba-solver, I think this is ready for merge now. Not sure if we want to do this for 24.11 right away, in which case I would advocate for a rc release sometime soon, accumulate feedback, and then proceed with 24.11 final by mid-end November? If we need to do some more work on the 24.9.x series we can always start a branch later, but I think 24.11 should be libmamba 2+ only. WDYT?

[jaimergp]

Once conda/conda#13784 is merged, I can revert the CI changes so we point to conda/conda@main again.

[jezdez]

LGTM! Thank you @jaimergp 🥳