Feature tile download retry

[dugalh]

Features:

• Improve download reliability by retrying corrupt or incomplete tiles (closes #22).
• Use timeouts on download Requests session to prompt retries.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 96.77419% with 3 lines in your changes missing coverage. Please review.

Project coverage is 91.69%. Comparing base (6f7f062) to head (03d7eaf). Report is 36 commits behind head on main.

Files with missing lines	Patch %	Lines
geedim/tile.py	96.96%	2 Missing :warning:
geedim/cli.py	91.66%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #23 +/- ## ========================================== + Coverage 91.08% 91.69% +0.60% ========================================== Files 13 13 Lines 1593 1613 +20 ========================================== + Hits 1451 1479 +28 + Misses 142 134 -8 ```

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