feat(search): added default support and test

[Sakthieswaran-tech]

• Show default value when input is empty.
• Pressing Tab fills the prompt with default or selected choice.
• Added test to verify default display, prefill behavior, and correct selection.

[codecov[bot]]

Codecov Report

:x: Patch coverage is 86.36364% with 3 lines in your changes missing coverage. Please review. :warning: Please upload report for BASE (main@6963b18). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
packages/search/src/index.ts	86.36%	3 Missing :warning:

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1915   +/-   ##
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  Coverage        ?   94.72%           
=======================================
  Files           ?       37           
  Lines           ?     1554           
  Branches        ?      461           
=======================================
  Hits            ?     1472           
  Misses          ?       80           
  Partials        ?        2           

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[Sakthieswaran-tech]

Hi @SBoudrias Just a gentle reminder — I pushed the requested review changes a few days ago. Whenever you get time, could you please take another look and let me know if anything else is needed? Thanks!