object server: resolve log error TODOs for remote node operations

[Copilot]

The object server gained internal logic in #3097 but had no logging, leaving four // TODO: log error stubs in remote-forwarding paths where failures were silently swallowed or only surfaced as returned errors.

Changes

• putStream: Added log *zap.Logger field; plumbed from Server via newIntermediatePutStream. sendToRemoteNode now warns on per-connection failure inside ForAnyGRPCConn.
• convertHeadPrm: Added log *zap.Logger parameter; transport func warns when getHeaderFromRemoteNode fails on a connection attempt.
• convertGetPrm: Added log *zap.Logger parameter; transport func warns when continueWithConn fails on a connection attempt.
• searchOnRemoteNode: Uses existing s.log to warn when searchOnRemoteAddress fails on a connection attempt.

All four sites log at Warn level — ForAnyGRPCConn may retry on another endpoint, so these are per-connection failures, not necessarily fatal outcomes.

• Fixes Add logging to object server #3098

[roman-khimov]

I think all of these are Debug level. Failure to perform some action on remote node is normal in general for many reasons and we can't spam logs in this case.

Open to other suggestions.

[codecov]

Codecov Report

❌ Patch coverage is 11.11111% with 16 lines in your changes missing coverage. Please review.
✅ Project coverage is 30.10%. Comparing base (f8cb96f) to head (9292593).
⚠️ Report is 4 commits behind head on master.

Files with missing lines	Patch %	Lines
pkg/services/object/server.go	11.11%	16 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4142      +/-   ##
==========================================
+ Coverage   29.78%   30.10%   +0.31%     
==========================================
  Files         678      679       +1     
  Lines       40860    40897      +37     
==========================================
+ Hits        12171    12310     +139     
+ Misses      28689    28587     -102     

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[End-rey]

I tend to agree: Debug seems more appropriate here to avoid excessive warning logs from expected remote-node failures.

[roman-khimov]

@copilot, make these messages debug level as per review comments

[Copilot]

@copilot, make these messages debug level as per review comments

Done — all four log sites changed from Warn to Debug in the latest commit.