Add Redis Streams XREAD/XREADGROUP benchmark test suites

[paulorsousa]

This PR introduces comprehensive benchmark test suites for Redis Streams functionality, covering both simple stream reading and consumer group-based distributed processing scenarios with large-scale datasets.

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Tests Added

1. memtier_benchmark-stream-10M-entries-xread-count-100.yml

• Purpose: Tests XREAD performance with batch reading on large datasets
• Dataset: Pre-loads 10M stream entries using XADD (100-byte messages)
• Test: XREAD COUNT 100 operations reading from stream beginning
• Use Case: Large-scale simple stream consumption without consumer groups

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2. memtier_benchmark-stream-10M-entries-xreadgroup-count-100.yml

• Purpose: Tests XREADGROUP performance with consumer groups on large datasets
• Dataset: Pre-loads 10M stream entries, creates consumer group test-group
• Test: XREADGROUP operations with COUNT 100 for distributed processing
• Use Case: Large-scale consumer group-based stream processing

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3. memtier_benchmark-stream-concurrent-xadd-xreadgroup-70-30.yml

• Purpose: Tests concurrent producer/consumer workloads in real-time scenarios
• Dataset: Starts with 500K pre-loaded stream entries
• Test: Mixed workload with 70% XADD (producers) and 30% XREADGROUP (consumers)
• Consumer Setup: Dual consumers (consumer1 / consumer2) with 15% ratio each for load distribution
• Use Case: Real-world streaming applications with continuous production and consumption

[fcostaoliveira]

thank you @paulorsousa !