Add context to bgpkit warning messages

[ties]

When reading logs, lines like

WARN worker-13 mrt_file: not enough bytes: input bytes left - 3, want to read - 1024; skipping ^]]3mfile=./2025-11-05/rrc00/2025.11/updates.20251105.0600.gz
WARN worker-26 mrt_file: not enough bytes: input bytes left - 3, want to read - 1024; skipping ^]]3mfile=./2025-11-05/rrc15/2025.11/updates.20251105.0605.gz

Made me think the full file was skipped, while only the attributes for this message were skipped.

I think adding context to the warning messages clarifies them.

[codecov]

Codecov Report

❌ Patch coverage is 41.66667% with 7 lines in your changes missing coverage. Please review.
✅ Project coverage is 90.70%. Comparing base (da6b8dd) to head (a2acfdb).

Files with missing lines	Patch %	Lines
src/parser/bgp/attributes/attr_14_15_nlri.rs	50.00%	2 Missing ⚠️
src/parser/bgp/messages.rs	0.00%	2 Missing ⚠️
src/parser/bmp/messages/headers.rs	0.00%	2 Missing ⚠️
...rser/mrt/messages/table_dump_v2/rib_afi_entries.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #274   +/-   ##
=======================================
  Coverage   90.70%   90.70%           
=======================================
  Files          84       84           
  Lines       15496    15496           
=======================================
  Hits        14056    14056           
  Misses       1440     1440           

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