Add local TCP/UDP probe listener and MTR diagnostics to CLI and analysis

[ehsanking]

Motivation

• Provide an on-server TCP/UDP echo listener to help Iran-side probing without extra packages and surface MTR-based connectivity health in analysis output.
• Improve connectivity scoring and reporting by incorporating a lightweight MTR check (loss %) to better indicate path quality.
• Update documentation to show listener usage examples and clarify MTR results in outputs and examples.

Description

• Implemented a startProbeListener helper and new listener CLI command in cli.js to run TCP and/or UDP echo listeners using net and dgram, with --host, --port, and --protocol options.
• Added MTR execution and parsing to iran_connectivity.js by introducing mtrAvailable, mtrLossPercent, mtrRawSample, and updating stageResults.mtr and the connectivity scoring logic to award points based on loss thresholds.
• Updated CLI reporting in cli.js to display an MTR badge and loss percent in summary and per-provider details, and added the listener and MTR notes to README.md including example commands and quick probe snippets.
• Minor README examples adjusted (e.g. jq example filtering by ports["443"]) and the command reference now lists listener.

Testing

• Ran the repository automated test suite with npm test and the suite completed successfully.
• Ran the project's linter/formatting checks via npm run lint which passed without errors.
• Executed the CLI smoke test node cli.js --help in CI to validate command registration and it succeeded.

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[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Keep bestConnection when rendering MTR provider summary

In printDetailedReport, the successful-provider summary now derives the MTR badge/loss from provider.bestConnection, but entries in results.successfulProviders are populated without a bestConnection field (they only carry provider/name/count/score in runAnalysis). When --detailed output is shown, this makes every successful provider display MTR: ✗, loss: N/A regardless of real MTR results, so the newly added MTR summary is systematically incorrect.

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