experiment: Refactor funnel implementation

[michaeldowseza]

Description

This simplifies the existing funnel instrumentation by removing the nested funnel abstraction contexts to define a funnel step and substep and opts for a controller pattern instead where the funnel status is maintained in regular classes.

Related links, issue #, if available: n/a

How has this been tested?

Review checklist

The following items are to be evaluated by the author(s) and the reviewer(s).

Correctness

• Changes include appropriate documentation updates.
• Changes are backward-compatible if not indicated, see CONTRIBUTING.md.
• Changes do not include unsupported browser features, see CONTRIBUTING.md.
• Changes were manually tested for accessibility, see accessibility guidelines.

Security

• If the code handles URLs: all URLs are validated through the checkSafeUrl function.

Testing

• Changes are covered with new/existing unit tests?
• Changes are covered with new/existing integration tests?

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[codecov]

Codecov Report

Attention: Patch coverage is 78.72340% with 120 lines in your changes missing coverage. Please review.

Project coverage is 95.51%. Comparing base (7693793) to head (c230525).
Report is 14 commits behind head on main.

Files with missing lines	Patch %	Lines
src/internal/analytics/funnel/funnel.ts	71.05%	33 Missing ⚠️
src/internal/analytics/funnel/funnel-substep.ts	50.00%	27 Missing ⚠️
src/alert/index.tsx	21.05%	15 Missing ⚠️
src/internal/analytics/funnel/funnel-base.ts	77.77%	12 Missing ⚠️
src/internal/analytics/funnel/funnel-step.ts	82.00%	9 Missing ⚠️
src/wizard/analytics/funnel/index.tsx	73.07%	7 Missing ⚠️
src/form/analytics/funnel/index.tsx	80.00%	6 Missing ⚠️
src/internal/analytics/contexts/funnel-context.tsx	66.66%	5 Missing ⚠️
src/modal/analytics/funnel/index.tsx	90.90%	3 Missing ⚠️
src/form-field/analytics/funnel/index.tsx	90.00%	1 Missing ⚠️
... and 2 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2893      +/-   ##
==========================================
- Coverage   96.21%   95.51%   -0.70%     
==========================================
  Files         761      771      +10     
  Lines       21490    21625     +135     
  Branches     7359     7377      +18     
==========================================
- Hits        20676    20656      -20     
- Misses        761      960     +199     
+ Partials       53        9      -44     

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