feat: replace anyhow with proper error variants in message stores

[davidsteiner]

No description provided.

[codecov]

Codecov Report

❌ Patch coverage is 80.68182% with 17 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.36%. Comparing base (74cb1ca) to head (9143732).

Files with missing lines	Patch %	Lines
crates/hotfix/src/store/file.rs	86.27%	7 Missing ⚠️
crates/hotfix/src/session.rs	58.33%	5 Missing ⚠️
crates/hotfix/src/store/mongodb.rs	83.33%	4 Missing ⚠️
crates/hotfix/src/session_schedule.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #279      +/-   ##
==========================================
- Coverage   89.48%   89.36%   -0.12%     
==========================================
  Files          84       83       -1     
  Lines        8004     8031      +27     
==========================================
+ Hits         7162     7177      +15     
- Misses        842      854      +12     

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