feat: add platform-wide NUMAFLOW_LOG_LEVEL support

[adarsh0728]

What this PR does / why we need it

• Users need a way to raise log levels for daemon and controller pods to reduce log noise.
• Adds NUMAFLOW_LOG_LEVEL support for Go components using zap log levels.
• Documents Go and Rust log-level controls, including examples for daemon, controller, webhook, server, ISB jobs, vertex, MonoVertex.
• Moves noisy idle MonoVertex rater metric logs from info to debug.

[codecov]

Codecov Report

❌ Patch coverage is 94.52055% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 82.69%. Comparing base (284552f) to head (4e5c520).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
rust/numaflow/src/setup_tracing.rs	92.45%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3410      +/-   ##
==========================================
+ Coverage   82.58%   82.69%   +0.11%     
==========================================
  Files         307      308       +1     
  Lines       75655    76141     +486     
==========================================
+ Hits        62476    62963     +487     
+ Misses      12621    12619       -2     
- Partials      558      559       +1     

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[yhl25]

I think we should just use DAEMON_LOG_LEVEL and not NUMAFLOW_LOG_LEVEL

[yhl25]

Should we explicitly mention CONTROLLER_LOG_LEVEL(daemon, controller etc) and DATAPLANE_LOG_LEVEL (should work like RUST_LOG)

[BulkBeing]

I think a single variable would be better, like NUMAFLOW_LOG_LEVEL.
We won't need to use DAEMON_LOG and NUMAFLOW_LOG at the same time for a single container anyway right?

Even if there is a situation like this, what do you think about treating them like components/modules and use Rust's log/tracing syntax:

NUMAFLOW_LOG_LEVEL=debug,builtin_udf=warn

[yhl25]

makes sense, lets go with one single log level env.