download: more consistent and exhaustive logging, new `DANDI_DEVEL_AGGRESSIVE_RETRY` mode, respect (?) Retry-After

[yarikoptic]

It was originally developed as part of the PR but derailed into fixing/robustifying download functionality. So sits on top of

• 1499

TODOs

• [x] make sure testing passes (added test revealed some odd behavior on Windows)
• possibly fold in here fixup for download to do full file checksumming if download was resumed: https://github.com/dandi/dandi-cli/issues/1528

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 72.72727% with 30 lines in your changes missing coverage. Please review.

Project coverage is 88.51%. Comparing base (6aa414c) to head (7f97394). Report is 25 commits behind head on master.

Files with missing lines	Patch %	Lines
dandi/download.py	35.71%	27 Missing :warning:
dandi/cli/command.py	0.00%	1 Missing :warning:
dandi/dandiapi.py	80.00%	1 Missing :warning:
dandi/tests/test_download.py	98.33%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #1509 +/- ## ========================================== - Coverage 88.58% 88.51% -0.08% ========================================== Files 78 78 Lines 10589 10689 +100 ========================================== + Hits 9380 9461 +81 - Misses 1209 1228 +19 ``` | [Flag](https://app.codecov.io/gh/dandi/dandi-cli/pull/1509/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dandi) | Coverage Δ | | |---|---|---| | [unittests](https://app.codecov.io/gh/dandi/dandi-cli/pull/1509/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dandi) | `88.51% <72.72%> (-0.08%)` | :arrow_down: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dandi#carryforward-flags-in-the-pull-request-comment) to find out more.

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[yarikoptic]

FTR: rebased/force-pushed to get a fresh run of tests after recent changes and drop of 3.8 support.

[yarikoptic]

ok

• windows: filed https://github.com/pytest-dev/pytest/issues/12964 . Unfortunately I think we are doomed to skip it on windows for now to not cause that issue until it is resolved one way or another.
• vcr -- delayed import and not used on 3.9
• "dev" run -- https://github.com/hdmf-dev/hdmf-zarr/issues/235

overall -- we are "ready" here as testing concerned.

[github-actions[bot]]

:rocket: PR was released in 0.64.0 :rocket: