chore: byte index to read singularEvent, propagate payload func to processor pipeline

[Sidddddarth]

Description

Use byte index to get event payload and propagate same to processor pipeline steps.

Linear Ticket

Resolves PIPE-1717

Security

• The code changed/added as part of this pull request won't create any security issues with how the software is being used.

[codecov]

Codecov Report

Attention: Patch coverage is 85.07463% with 10 lines in your changes missing coverage. Please review.

Project coverage is 73.54%. Comparing base (f908e21) to head (f9498ae).

Files with missing lines	Patch %	Lines
processor/processor.go	84.84%	9 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5314      +/-   ##
==========================================
- Coverage   73.57%   73.54%   -0.03%     
==========================================
  Files         424      424              
  Lines       59935    59961      +26     
==========================================
+ Hits        44095    44098       +3     
- Misses      13370    13397      +27     
+ Partials     2470     2466       -4     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

---

🚨 Try these New Features:

• Flaky Tests Detection - Detect and resolve failed and flaky tests