Move SnapshotVersion and default config values to snapshot_config

[kskalski]

Problem

snapshot_config depends on constants and type from snapshot_utils that are directly used and related to config and which utils could easily import from config

Summary of Changes

• Move SnapshotVersion to snapshot_config
• Move default values for config to snapshot_config
• update all uses

(this change will allow a cleaner move of snapshot_config to new agave-snapshots crate added in #8382)

[codecov-commenter]

Codecov Report

❌ Patch coverage is 92.00000% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 83.1%. Comparing base (0199a3a) to head (1a3c594).
⚠️ Report is 2 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff            @@
##           master    #8487    +/-   ##
========================================
  Coverage    83.1%    83.1%            
========================================
  Files         840      840            
  Lines      367669   367668     -1     
========================================
+ Hits       305719   305870   +151     
+ Misses      61950    61798   -152     

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