Enhancements:
* Add `osx-arm64` as a recognized platform (#10128, #10134, #10137)
* Resign files modified during installation on ARM64 macOS (#10260)
* Add `__archspec` virtual package to identify CPU microarchitecture (#9930)
* Add `__unix` and `__win` virtual packages (#10214)
* Add `--no-capture--output` option to `conda run` (#9646)
* Add `--live-stream` option to `conda run` (#10270)
* Export and import environment variables set using `conda env config` (#10169)
* Cache repodata from `file://` channels (#9730)
* Do not relink already-installed packages (#10208)
* Speed up JSON formatting in logz module (#10189)

Bug fixes:
* Stop `env remove --dry-run` from actually removing environments (#10261)
* Virtual package requirements are now considered by the solver (#10057)
* Fix cached filename processing when using only tar.bz2 (#10193)
* Stop showing solver hints about CUDA when it is not a dependency (#10275)
* Ignore virtual packages when checking environment consistency (#10196)
* Fix `config --json` output errors in certain circumstances (#10194)
* More consistent error handling by `conda shell` (#10238)
* Bump vendored version of tqdm to fix various threading and I/O bugs (#10266)

Docs:
* Correctly state default `/AddToPath` option in Windows installer (#10179)
* Fix typos in `--repodata-fn` help text (#10279)

Miscellaneous:
* Update CI infrastructure to use GitHub Actions (#10176, #10186, #10234)
* Update README badge to show GitHub Actions status (#10254)

Contributors
* @AlbertDeFusco
* @angloyna
* @bbodenmiller
* @casperdcl
* @chenghlee
* @chrisburr
* @cjmartian
* @dhirschfeld
* @ericpre
* @gabrielcnr
* @InfiniteChai
* @isuruf
* @jjhelmus
* @LorcanHamill
* @maresb
* @mingwandroid
* @mlline00
* @xhochy
* @ydmytryk