feat(cel-shed): Add blob.Submit and blob.Retrieve latency monitor tool

[renaynay]

Adds blob.Submit and blob.Retrieve latency monitor tool via latency-monitor

./cel-shed latency-monitor <node ip> <node port> <auth token> <metrics endpoint> 

• works with either LN or BN
• creates rpc client + submits + retrieves blobs
• blob is currently 7000 bytes but will make that configurable later

[codecov-commenter]

Codecov Report

❌ Patch coverage is 4.76190% with 140 lines in your changes missing coverage. Please review.
✅ Project coverage is 35.78%. Comparing base (2469e7a) to head (43cd009).
⚠️ Report is 627 commits behind head on main.

Files with missing lines	Patch %	Lines
cmd/cel-shed/latency_monitor.go	0.00%	116 Missing ⚠️
libs/utils/telemetry.go	0.00%	22 Missing ⚠️
cmd/cel-shed/main.go	0.00%	1 Missing ⚠️
cmd/flags_misc.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4718      +/-   ##
==========================================
- Coverage   44.83%   35.78%   -9.05%     
==========================================
  Files         265      307      +42     
  Lines       14620    20625    +6005     
==========================================
+ Hits         6555     7381     +826     
- Misses       7313    12287    +4974     
- Partials      752      957     +205     

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