refactor(control-plane): remove EC2 assumptions

[edersonbrilhante]

Description

Depends on #5307.

Removes EC2-specific assumptions from generic control-plane tests and the local pool invocation. Scale-up and scale-down test doubles now model provider capability factories without owning a provider type, partial creation tests use provider-neutral runner terminology, and pool events rely on the optional provider type's default behavior.

The scale-up provider-selection test remains as integration coverage, but asserts the public defaultComputeProvider contract instead of the concrete EC2 value. The provider-type unit tests remain responsible for the concrete default mapping.

Test Plan

• Ran the affected scale-up, scale-down, and Lambda wrapper suites: 253 tests passed.
• Ran the complete Lambda Vitest suite: 819 tests passed.
• Ran the control-plane TypeScript type-check.
• Ran ESLint and Prettier checks for all changed files.
• Ran git diff --check.
• Verified the four scoped files contain no EC2 references.

Related Issues

None.

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None