chore: move h-scale lifecycle into ITS

[leon-ape]

Summary

• Move horizontal scale lifecycle ownership into the workload controller.
• Add pod-centric lifecycle state and execution for data load, member join, and member leave in InstanceSet.
• Turn component into a compatibility shell that translates intent and consumes InstanceSet state, while removing the old replicas-status and task-event based execution path.

[apecloud-bot]

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[leon-ape]

/nopick

[codecov]

Codecov Report

❌ Patch coverage is 63.13725% with 94 lines in your changes missing coverage. Please review.
✅ Project coverage is 51.86%. Comparing base (edbff89) to head (5c8daef).

Files with missing lines	Patch %	Lines
...oller/instanceset/reconciler_instance_alignment.go	57.14%	50 Missing and 19 partials ⚠️
apis/workloads/v1/instanceset_types.go	0.00%	10 Missing ⚠️
...ers/apps/component/transformer_component_status.go	25.00%	4 Missing and 2 partials ⚠️
pkg/controller/builder/builder_instance_set.go	0.00%	3 Missing ⚠️
pkg/controller/lifecycle/lfa_data.go	66.66%	2 Missing and 1 partial ⚠️
...ps/component/transformer_component_workload_ops.go	71.42%	1 Missing and 1 partial ⚠️
...s/apps/component/transformer_component_workload.go	66.66%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #10105      +/-   ##
==========================================
+ Coverage   51.60%   51.86%   +0.25%     
==========================================
  Files         525      524       -1     
  Lines       58397    57980     -417     
==========================================
- Hits        30138    30069      -69     
+ Misses      25305    24970     -335     
+ Partials     2954     2941      -13     

Flag	Coverage Δ
unittests	51.86% <63.13%> (+0.25%)	⬆️

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