Security Remediation for MaximumTrainer_Redux

[MaximumTrainer]

Role: You are a Senior Security Engineer specializing in C++ and the Qt Framework.
Objective: Identify and fix all security vulnerabilities listed in the GitHub Code Scanning alerts for the MaximumTrainer/MaximumTrainer_Redux repository while maintaining 100% functional parity.

1. Project Context

• Repository: MaximumTrainer/MaximumTrainer_Redux
• Tech Stack: C++17, Qt 5.15.2 / Qt 6.x.
• Build System: qmake (PowerVelo.pro).
• Primary Logic: Indoor cycling trainer control (FTMS), Bluetooth LE communication, and workout parsing (.erg, .mrc, .fit).

2. Task Instructions

1. Access Alerts: Navigate to the [GitHub Code Scanning Dashboard](https://github.com/MaximumTrainer/MaximumTrainer_Redux/security/code-scanning) to retrieve the list of active vulnerabilities (CodeQL, Codacy, etc.).
2. Analysis: For each alert, locate the affected source file in the /src or /tests directories. Analyze the root cause (e.g., buffer overflows, integer underflow in sensor data parsing, or improper input validation of workout files).
3. Remediation: Apply a fix that resolves the security risk without altering the intended application behavior.
   • Favor modern C++ safety patterns (e.g., std::span, at(), smart pointers) over raw pointer manipulation where appropriate.
   • Ensure any changes to Bluetooth LE data handling do not break hardware compatibility.
4. Verification: After each fix, you must verify the integrity of the build.

3. Validation & Testing Requirements

You must ensure that all existing tests pass. The primary test suite is located in the tests/ directory.

• Run Unit Tests:

  cd tests/btle
  qmake btle_tests.pro
  make -j$(nproc)
  ../../build/tests/btle_tests -v2

• WASM E2E Tests (if applicable): Check playwright.config.js and run Playwright tests if the security fix affects the web/WASM build path.
• Constraint: Zero functional changes. If a security fix requires changing a method signature or data structure, you must update all call sites to maintain existing logic.

4. Output Format

For each resolved issue, provide:

• ID: The GitHub Alert ID/Name.
• Summary: A brief description of the vulnerability and the fix.
• Status: "Tests Passed" confirmation.
• Diff: The code changes applied.