Add static file server to http service

[sandreae]

Use https://docs.rs/tower-http/latest/tower_http/services/struct.ServeDir.html# to add a static file server to the http service which serves content from $HOME/.local/share/aquadoggo/blobs by default.

📋 Checklist

• Add tests that cover your changes
• Add this PR to the Unreleased section in CHANGELOG.md
• Link this PR to any issues it closes
• New files contain a SPDX license header

[codecov]

Codecov Report

Patch coverage: 96.42% and no project coverage change.

Comparison is base (d5ba55d) 91.95% compared to head (2b400ef) 91.96%.

Additional details and impacted files

@@           Coverage Diff           @@
##            blobs     #480   +/-   ##
=======================================
  Coverage   91.95%   91.96%           
=======================================
  Files         100      100           
  Lines       15914    15935   +21     
=======================================
+ Hits        14634    14654   +20     
- Misses       1280     1281    +1     

Files Changed	Coverage Δ
aquadoggo/src/config.rs	46.93% <80.00%> (+3.75%)	⬆️
aquadoggo/src/graphql/mutations/publish.rs	98.68% <100.00%> (ø)
aquadoggo/src/http/context.rs	100.00% <100.00%> (ø)
aquadoggo/src/http/service.rs	98.80% <100.00%> (+0.21%)	⬆️
aquadoggo/src/test_utils/client.rs	76.47% <100.00%> (ø)

... and 3 files with indirect coverage changes

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