feat: track progress

[shizhMSFT]

Important

This PR resolves #839 and is experimental.

This PR introduce a new package progress to track the progress of reading content.

[shizhMSFT]

Discussions should go to #839

[codecov]

Codecov Report

Attention: Patch coverage is 40.57971% with 41 lines in your changes missing coverage. Please review.

Project coverage is 75.32%. Comparing base (a80f219) to head (e05a45d).

Files with missing lines	Patch %	Lines
progress/tracker.go	44.44%	32 Missing and 3 partials ⚠️
progress/manager.go	0.00%	6 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #852      +/-   ##
==========================================
- Coverage   75.72%   75.32%   -0.40%     
==========================================
  Files          63       65       +2     
  Lines        6011     6080      +69     
==========================================
+ Hits         4552     4580      +28     
- Misses       1078     1116      +38     
- Partials      381      384       +3     

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