fix: keep proxies opaque in util.inspect when showProxy is false

[azadgupta1]

Currently, util.inspect unwraps proxies even when showProxy is false,
which can trigger traps for nested proxies and lead to unexpected errors.

This change:

• Treats proxies as opaque when showProxy is false.
• Keeps the original target for internal inspection.
• Adds a regression test to ensure that accessing nested proxies does not throw when showProxy is disabled.

Refs: #61061

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.42%. Comparing base (900d329) to head (35e258c).
⚠️ Report is 159 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #61068 +/- ##
==========================================
- Coverage 88.55% 88.42% -0.14% 
==========================================
Files 703 703 Lines 208260 208550 +290 Branches 40155 40135 -20 ==========================================
- Hits 184430 184410 -20 - Misses 15837 16148 +311 + Partials 7993 7992 -1 

Files with missing lines	Coverage Δ
lib/internal/util/inspect.js	99.67% <100.00%> (+0.03%)	⬆️

... and 93 files with indirect coverage changes

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[benjamingr]

I think this is the opposite of what @jasnell wanted?

[BridgeAR]

This actually does not fix the issue, while it fails many tests

[BridgeAR]

Closing in favor of #61077