Release v1.0.0: finalize lightweight MEC simulator

[Ryan-Yii]

Summary

This pull request prepares mec-offloading-visualizer for its first stable
release:

v1.0.0 — Lightweight MEC Simulation and Visualization

The project remains focused on lightweight, reproducible comparison of
local-only, edge-first, and cloud-first MEC offloading baselines.

Main changes

• strengthened configuration validation and error reporting;
• added explicit handling for invalid strategies and empty execution tiers;
• expanded automated testing from 10 to 40 tests;
• verified deterministic scenario generation and multi-seed experiments;
• added regression tests for latency, energy, cost, and deadline calculations;
• improved CLI failure handling and portable output behavior;
• added headless plotting tests;
• unified package versioning at 1.0.0;
• consolidated dependencies in pyproject.toml;
• expanded GitHub Actions to Python 3.10, 3.11, and 3.12;
• rewrote the README with reproducibility instructions and modeling limits;
• added design, reproducibility, changelog, and release documentation;
• regenerated example CSV files and figures from the documented configuration.

Verification

Local verification was completed using Python 3.12.13:

• 40 passed with no pytest warnings;
• source distribution and wheel built successfully;
• the wheel was installed in a clean virtual environment;
• pip check reported no broken requirements;
• the installed package reported version 1.0.0;
• the installed CLI successfully completed a three-task smoke experiment;
• non-empty CSV files and figures were generated;
• git diff --check origin/main...HEAD passed.

Scope

This release does not add:

• task queues;
• dynamic node load;
• microservices;
• distributed workers;
• failure recovery;
• Docker or Kubernetes;
• reinforcement-learning scheduling.

Those capabilities are reserved for a separate future distributed MEC
scheduling project.