Standardize code formatting across Python, Go, C++, and Java

[Copilot]

Applied language-standard formatters to establish consistent code style across the repository.

Changes

Python (20 files)

• Applied autopep8 --aggressive
• Fixed syntax error: missing colon in day7/solution.py
• Fixed invalid regex escape sequences (raw strings)
• 126/176 issues resolved; remaining 50 are non-critical (line length, unused imports)

Go (5 files)

• Applied gofmt
• Removed empty function declaration in day11/main_test.go

C++ (5 files)

• Applied clang-format
• Standardized indentation and comment spacing

Java (31 files)

• Applied google-java-format
• Follows Google Java Style Guide

Repository

• Updated .gitignore to exclude binaries and build artifacts (*.o, _codeql_*, compiled binaries)

---

✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.