Add a tlog-policy parser

[BenBirt]

No description provided.

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[codecov-commenter]

Codecov Report

❌ Patch coverage is 92.55319% with 14 lines in your changes missing coverage. Please review.
✅ Project coverage is 79.97%. Comparing base (fa00c16) to head (d94901d).
⚠️ Report is 180 commits behind head on main.

Files with missing lines	Patch %	Lines
policy/tlog_policy.go	92.55%	7 Missing and 7 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #269      +/-   ##
==========================================
- Coverage   82.57%   79.97%   -2.60%     
==========================================
  Files           5        9       +4     
  Lines         241      884     +643     
==========================================
+ Hits          199      707     +508     
- Misses         30       97      +67     
- Partials       12       80      +68     

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[mhutchinson]

Looks good to me, but I'd like to have @AlCutter approve too.