fix: ability to limit http connections and pull concurrency

[ajcasagrande]

AIPERF_HTTP_CONNECTION_LIMIT

[Copilot]

Pull Request Overview

This PR introduces the ability to configure HTTP connection limits and worker pull concurrency through the environment variable AIPERF_HTTP_CONNECTION_LIMIT. The change moves away from hardcoded connection limits to a configurable system that defaults to 2500 connections.

• Adds AIPERF_HTTP_CONNECTION_LIMIT environment variable configuration
• Updates HTTP client defaults to use the configurable limit instead of hardcoded values
• Sets worker pull concurrency to match the HTTP connection limit to prevent oversubscription

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
aiperf/common/constants.py	Adds the new AIPERF_HTTP_CONNECTION_LIMIT constant that reads from environment
aiperf/clients/http/defaults.py	Updates HTTP client defaults to use the configurable limit and sets per-host limit to 0
aiperf/workers/worker.py	Configures worker pull concurrency to match HTTP connection limit
tests/clients/http/test_tcp_connector.py	Updates test assertions to use the new constant and expect per-host limit of 0

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[biswapanda]

lgtm !