fix(docs): explain manual pagination and add usage sample

[AVaksman]

• Ensure the tests and linter pass
• Code coverage does not decrease (if any source code was changed)
• Appropriate docs were updated (if necessary)

Fixes #1277

[codecov]

Codecov Report

Merging #1317 (3378b60) into master (642a9df) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #1317   +/-   ##
=======================================
  Coverage   99.00%   99.00%           
=======================================
  Files          14       14           
  Lines       11775    11799   +24     
  Branches      593      524   -69     
=======================================
+ Hits        11658    11682   +24     
  Misses        117      117           

Impacted Files	Coverage Δ
src/bucket.ts	99.53% <100.00%> (+<0.01%)	⬆️
src/storage.ts	100.00% <100.00%> (ø)

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[snippet-bot]

Here is the summary of changes.

You added 1 region tag.

• storage_list_files in samples/listFilesPaginate.js

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[shaffeeullah]

@AVaksman can this be merged?

[AVaksman]

@AVaksman can this be merged?
Yes, it is ready to be merged.
Thank you