chore: Add test run entity (no-changelog)

[burivuhster]

Summary

To store the status and results of each test run we need a new DB entity.
This PR:

• adds a new table for storing test runs
• adds typeorm entity and repository
• creates a new test run entry on each test run, updates it's status during workflow test execution

Related Linear tickets, Github issues, and Community forum posts

• https://linear.app/n8n/issue/AI-431/[db]-test-run
• feat(core): Run evaluation workflow per each test case (no-changelog) #11757

Review / Merge checklist

• PR title and summary are descriptive. (conventions)
• Docs updated or follow-up ticket created.
• Tests included.
• PR Labeled with release/backport (if the PR is an urgent fix that needs to be backported)

[codecov]

Codecov Report

Attention: Patch coverage is 85.98131% with 15 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
packages/cli/src/databases/entities/test-run.ee.ts	66.66%	0 Missing and 4 partials ⚠️
...src/databases/repositories/execution.repository.ts	0.00%	4 Missing ⚠️
...c/evaluation/test-runner/test-runner.service.ee.ts	94.66%	0 Missing and 4 partials ⚠️
.../src/databases/repositories/test-run.repository.ts	66.66%	2 Missing ⚠️
...i/src/evaluation/test-definitions.controller.ee.ts	88.88%	0 Missing and 1 partial ⚠️

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