feat: add RawEntryReader and OneshotWalEntryReader trait

[WenyXu]

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#4026

What's changed and what's your intention?

Add RawEntryReader and OneShotWalEntryReader trait

Checklist

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR requires documentation updates.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 40 lines in your changes are missing coverage. Please review.

Project coverage is 85.13%. Comparing base (a3a2c8d) to head (a3155e3).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4027      +/-   ##
==========================================
- Coverage   85.45%   85.13%   -0.32%     
==========================================
  Files         980      980              
  Lines      170181   170221      +40     
==========================================
- Hits       145435   144926     -509     
- Misses      24746    25295     +549     

[v0y4g3r]

LGTM