chore: additional clippy fixes

[reubeno]

No description provided.

[Copilot]

Pull Request Overview

This PR addresses additional clippy (Rust linter) warnings and improves code quality. The changes focus on applying clippy suggestions to make the codebase more idiomatic and efficient.

• Replace to_string() calls with more efficient clone() operations on existing strings
• Refactor variable declarations to use more idiomatic patterns
• Update match patterns to use Self:: instead of explicit enum names
• Add clippy allow attributes for specific cases where warnings are acceptable

Reviewed Changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
xtask/src/main.rs	Add backticks around shell names in documentation comments
brush-parser/src/error.rs	Replace enum patterns with Self:: and add clippy allow attribute
brush-core/src/variables.rs	Replace to_string() with clone() for existing string
brush-core/src/shell.rs	Replace map_or with map_or_else for lazy evaluation
brush-core/src/completion.rs	Replace to_string() with clone() for existing string
brush-core/src/builtins/set.rs	Add clippy allow attribute for useless_let_if_seq
brush-core/src/builtins/return_.rs	Refactor variable declaration to use if-let expression
brush-core/src/builtins/exit.rs	Refactor variable declaration to use if-let expression
.github/workflows/ci.yaml	Add --workspace flag to clippy command

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[github-actions]

Test Results

    3 files     20 suites   5m 4s ⏱️
  873 tests   873 ✅ 0 💤 0 ❌
2 599 runs  2 599 ✅ 0 💤 0 ❌

Results for commit af27462.

♻️ This comment has been updated with latest results.

[github-actions]

Performance Benchmark Report

Benchmark name	Baseline (μs)	Test/PR (μs)	Delta (μs)	Delta %
clone_shell_object	17.32 μs	17.19 μs	-0.13 μs	🟢 -0.74%
eval_arithmetic	0.14 μs	0.15 μs	0.01 μs	⚪ Unchanged
expand_one_string	1.91 μs	1.89 μs	-0.02 μs	⚪ Unchanged
for_loop	22.23 μs	21.94 μs	-0.29 μs	⚪ Unchanged
function_call	2.58 μs	2.38 μs	-0.20 μs	⚪ Unchanged
instantiate_shell	54.44 μs	54.47 μs	0.03 μs	⚪ Unchanged
instantiate_shell_with_init_scripts	23329.30 μs	22842.79 μs	-486.51 μs	⚪ Unchanged
parse_bash_completion	1717.39 μs	1718.85 μs	1.46 μs	⚪ Unchanged
parse_sample_script	1.86 μs	1.88 μs	0.02 μs	🟠 +1.13%
run_echo_builtin_command	15.56 μs	15.54 μs	-0.02 μs	⚪ Unchanged
run_one_external_command	2428.72 μs	2285.09 μs	-143.62 μs	🟢 -5.91%
tokenize_sample_script	2.87 μs	2.75 μs	-0.11 μs	🟢 -4.01%

Code Coverage Report: Only Changed Files listed

Package	Base Coverage	New Coverage	Difference
brush-core/src/builtins/return_.rs	🟢 94.12%	🟢 93.33%	🔴 -0.79%
brush-core/src/jobs.rs	🔴 37.16%	🔴 43.58%	🟢 6.42%
Overall Coverage	🟢 72%	🟢 72.08%	🟢 0.08%

Minimum allowed coverage is 70%, this run produced 72.08%

Test Summary: bash-completion test suite

Outcome	Count	Percentage
✅ Pass	1310	62.11
❗️ Error	247	11.71
❌ Fail	180	8.53
⏩ Skip	358	16.97
❎ Expected Fail	13	0.62
✔️ Unexpected Pass	1	0.05
📊 Total	2109	100.00