feat: switch to builder API for declarative agent apps

[anchenyi]

https://msazure.visualstudio.com/Microsoft%20Teams%20Extensibility/_workitems/edit/30479992

[codecov]

Codecov Report

Attention: Patch coverage is 92.00000% with 6 lines in your changes missing coverage. Please review.

Project coverage is 90.23%. Comparing base (ad64394) to head (5431056).
Report is 11 commits behind head on dev.

Files with missing lines	Patch %	Lines
...kages/fx-core/src/component/m365/packageService.ts	92.00%	3 Missing and 3 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##              dev   #13056      +/-   ##
==========================================
+ Coverage   90.22%   90.23%   +0.01%     
==========================================
  Files         581      583       +2     
  Lines       34945    35037      +92     
  Branches     6778     6969     +191     
==========================================
+ Hits        31529    31616      +87     
- Misses       1489     1491       +2     
- Partials     1927     1930       +3     

Files with missing lines	Coverage Δ
...kages/fx-core/src/component/m365/packageService.ts	92.48% <92.00%> (+0.21%)	⬆️

... and 17 files with indirect coverage changes