Fix all clippy warnings across the workspace

[Copilot]

• Fix all clippy warnings across the workspace
• Apply cargo fmt formatting across the workspace

Problem

Running cargo clippy --workspace --all-targets -- -D warnings was failing with 46+ clippy errors across multiple crates, preventing the use of strict clippy checking in CI/CD pipelines.

Changes Made

Critical Structural Issues

• Fixed non-local impl blocks: Moved impl Environment for TestEnvironment blocks outside of functions in test modules across pet-conda, pet-poetry, and pet-pyenv crates
• Resolved unused imports: Made conditional imports (e.g., use super::* only for Windows builds) and removed unused PathBuf imports
• Fixed items after test modules: Moved public functions before test modules in pet-python-utils

API & Function Signature Improvements

• Parameter type optimization: Changed &String to &str in function parameters (5 instances)
• Slice usage: Replaced &Vec<T> with &[T] for better performance
• Error handling: Replaced expect(format!(...).as_str()) with unwrap_or_else(|| panic!(...)) to avoid unnecessary allocations

Code Style & Optimization

• Boolean assertions: Replaced assert_eq!(value, true/false) with assert!(value) or assert!(!value)
• Struct initialization: Used struct initialization syntax instead of Default::default() + field assignment
• Removed needless operations: Eliminated unnecessary .to_string() calls and PathBuf::from() conversions
• Consolidated logic: Combined identical if-else blocks that were handling known issues

Test Configuration

• Fixed conditional compilation: Replaced invalid feature = "ci" with proper #[test] attributes
• Formatting: Removed empty lines after outer attributes

Code Formatting

• Applied cargo fmt: Ran cargo fmt --all to ensure consistent formatting across all workspace crates
• Improved readability: Better line wrapping for multi-line expressions and consistent indentation

Verification

The following commands now pass without any warnings or errors:

cargo clippy --workspace --all-targets -- -D warnings
cargo build --workspace

All changes are minimal and surgical, preserving existing functionality while improving code quality, performance, and maintainability. No breaking changes were introduced.

Created from VS Code via the GitHub Pull Request extension.

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[karthiknadig]

@copilot Please also run cargo fmt

[Copilot]

@copilot Please also run cargo fmt

Done! Applied cargo fmt --all formatting across the workspace. The code now has consistent formatting and still passes all clippy checks and builds successfully. (commit 0982c56)