refactor: use stricter linting rules

[2bndy5]

• mandates no panicking code (eg. unwrap(), expect(), panic!(), etc) used in production; tests are allowed to panic.
• ensures all public API has a doc comment. Any public API missing a doc comment now has a one.
• collapsed single-file submodules into a normal submodule (eg. common_fs/mod.rs becomes just common_fs.rs)

Summary by CodeRabbit

• New Features

  • Added REST client helpers for debug checks and log-group start/end.

• Bug Fixes / Improvements

  • Safer comment generation with fallible error propagation.
  • Filtered out invalid zero line numbers when computing added-line ranges.
  • Tests adjusted to allow certain test-only unwrap/expect usage.

• Documentation

  • Expanded Rustdoc comments across CLI, error types, and tooling modules.

• Refactor

  • Hardened crate linting and made the git-related module internal.

[coderabbitai]

Walkthrough

This PR refactors lint policies from scattered module-level denials into centralized crate-level configuration, expands Rustdoc coverage across error types and CLI structures, improves error handling in RestClient by replacing unwrap calls with proper Result propagation, adds three new public RestClient methods for logging support, validates added-line numbers via NonZeroU32 in FileObj, and changes the git module from public to private.

Changes

Lint policy centralization, documentation, and error handling

Layer / File(s)	Summary
Clang tools data contract enhancements cpp-linter/src/clang_tools/clang_format.rs, cpp-linter/src/clang_tools/clang_tidy.rs, cpp-linter/src/clang_tools/mod.rs	FormatAdvice and TidyAdvice gain doc comments for their patched cache paths; clang-tools module Rustdoc expanded for CACHE_DIR, capture_clang_tools_output, ReviewComments helpers, and make_patch.
CLI docs and option structs cpp-linter/src/cli/mod.rs, cpp-linter/src/cli/structs.rs	Add docs for Verbosity variants, Cli flattened option groups and commands field; expand ClangParams, FeedbackInput, and LinesChangedOnly documentation; test clippy allows updated.
FileObj added-lines validation cpp-linter/src/common_fs.rs	Filter added_lines through NonZeroU32, refactor consolidate_numbers_to_ranges to accept non-zero input, and add test for single added line handling.
RestClient error handling and logging API cpp-linter/src/rest_client.rs	Add is_debug_enabled, start_log_group, end_log_group; make comment builders return Result and propagate errors with ?; include clang detail blocks only when versions present; map mutex poison to ClientError.
Crate-level lint policy & module visibility cpp-linter/src/lib.rs, cpp-linter/src/git.rs, cpp-linter/src/logger.rs, cpp-linter/src/main.rs, cpp-linter/src/run.rs	Introduce crate-level #![deny(...)] for selected clippy lints and missing_docs; remove pub from git module and adjust module/test-level lint attributes and cfg gating.
Comprehensive error documentation cpp-linter/src/error.rs	Add module-level Rustdoc and per-variant documentation for FileObjError, ClientError, ClangCaptureError, and ClangTaskError without changing types/signatures.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Possibly related PRs

• cpp-linter/cpp-linter-rs#52: Overlaps with added RestClient start_log_group/end_log_group behavior and log-grouping responsibilities.

Suggested labels

documentation, rust

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The PR title 'refactor: use stricter linting rules' directly and clearly summarizes the main change: implementing stricter linting rules across the codebase, which aligns with the PR objectives.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch stricter-linting

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[codecov]

Codecov Report

❌ Patch coverage is 92.59259% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 92.74%. Comparing base (ead918a) to head (9376992).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
cpp-linter/src/rest_client.rs	84.00%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #353      +/-   ##
==========================================
- Coverage   92.89%   92.74%   -0.16%     
==========================================
  Files          22       22              
  Lines        3380     3403      +23     
==========================================
+ Hits         3140     3156      +16     
- Misses        240      247       +7     

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.