Add support for bulk manager import

[stranske]

Why

Test Suite D, Test D2 - Auto-Label functional test.

Test Suite D, Test D2 - Auto-Label functional test.

Scope

Enable importing multiple manager records at once from CSV or JSON files to streamline onboarding.

Enable importing multiple manager records at once from CSV or JSON files to streamline onboarding.

Non-Goals

Not provided.

Tasks

• Create POST /api/managers/bulk endpoint
• Accept CSV file upload
• Accept JSON array in request body
• Validate all records before import
• Return import summary with success/failure counts
• Create POST /api/managers/bulk endpoint
• Accept CSV file upload
• Accept JSON array in request body
• Validate all records before import
• Return import summary with success/failure counts

Acceptance Criteria

• Can import 100+ managers in single request
• Invalid records logged but don't block valid ones
• Response includes detailed import report
• Can import 100+ managers in single request
• Invalid records logged but don't block valid ones
• Response includes detailed import report
• Test expectation: Should be auto-labeled as 'enhancement' - new feature request

Implementation Notes

Not provided.

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<summary>Original Issue</summary>

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