perf: Avoid redundant list operations in ListLike

[s-alexey]

• Removed list() casts and concatenations in __add__ and __radd__ methods of ListLike and NamedListLike containers.

[codecov]

Codecov Report

Attention: Patch coverage is 90.00000% with 1 line in your changes missing coverage. Please review.

Project coverage is 86.65%. Comparing base (f4f6035) to head (842e0ab).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
panel/layout/base.py	90.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #7764       +/-   ##
===========================================
+ Coverage   71.23%   86.65%   +15.41%     
===========================================
  Files         345      346        +1     
  Lines       52792    52791        -1     
===========================================
+ Hits        37609    45744     +8135     
+ Misses      15183     7047     -8136     

☔ View full report in Codecov by Sentry.
📢 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.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[hoxbro]

Thank you