Simplify datachain.lib.listing by reusing Cilent.scandir()

[rlamy]

Fixes #373

[cloudflare-workers-and-pages]

Deploying datachain-documentation with    Cloudflare Pages

Latest commit:	06d0061
Status:	✅  Deploy successful!
Preview URL:	https://1ef6443b.datachain-documentation.pages.dev
Branch Preview URL:	https://issue-373.datachain-documentation.pages.dev

View logs

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.74%. Comparing base (ed71afa) to head (06d0061).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #376      +/-   ##
==========================================
+ Coverage   86.67%   86.74%   +0.06%     
==========================================
  Files          92       92              
  Lines       10127    10072      -55     
  Branches     2057     2046      -11     
==========================================
- Hits         8778     8737      -41     
+ Misses        993      986       -7     
+ Partials      356      349       -7     

Flag	Coverage Δ
datachain	86.67% <100.00%> (+0.06%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[shcheklein]

Thanks @rlamy !

[ilongin]

Even though I wanted to to this exact thing at first, my understanding was that we need to move as much "core" logic to "user / lib" level as possible for listing/indexing (that was part of the requirement). For scandir it was kind of questionable whether it really needs to be in the Client or we can move it to "upper" level and since it basically has most of the codebase used in listing I decided to lift it up.
I'm not against this refactoring, just explaining the reasoning.

[rlamy]

my understanding was that we need to move as much "core" logic to "user / lib" level as possible for listing/indexing (that was part of the requirement).

I agree with that, and I think that this PR is part of it. IMO, we need to make Client independent of the core, and vice-versa, so it can become a completely app-level component. I've always understood that to be part of the plan for #33.