fix: resolve clippy warnings in container, git, and init modules

[bz00qa]

Summary

• Apply clippy suggestions carved out from feature PRs feat: native cross-platform hook for Windows support #551 and feat(read,git): add read diet mode and smarter git diff filtering #552 to keep those PRs focused on their stated scope
• container.rs: .last() → .next_back() (2 instances)
• git.rs: .map_or(false, ...) → .is_some_and(...) (2 instances), .last() → .next_back() (1 instance)
• init.rs: unnecessary format!() → .to_string() (1 instance), unnecessary & on &str parameters (2 instances)

Test plan

• cargo clippy --all-targets passes
• cargo test passes (937 passed, 2 pre-existing failures unrelated to these changes)
• No behavioral changes — pure clippy cleanup

🤖 Generated with Claude Code

[CLAassistant]

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[aeppling]

Hey

We are cleaning up the codebase and improving the project structure for better onboarding. As part of this effort, PR #826 reorganizes src/ from a flat layout into subfolders.

No logic changes — only file moves and import path updates.

What you need to do

Rebase your branch on develop when receiving this comment:

git fetch origin && git rebase origin/develop

Git detects renames automatically. If you get import conflicts, update the paths:

use crate::git;        // now: use crate::cmds::git::git;
use crate::tracking;   // now: use crate::core::tracking;
use crate::config;     // now: use crate::core::config;
use crate::init;       // now: use crate::hooks::init;
use crate::gain;       // now: use crate::analytics::gain;

Need help rebasing? Tag @aeppling

[pszymkowiak]

Closing this PR for inactivity — the CLA was never signed and there's been no activity since March. This isn't a judgment on the change itself.

If you'd still like to land it, just sign the CLA (https://cla-assistant.io/rtk-ai/rtk) and ping a maintainer to reopen — happy to pick it back up. Thanks for the contribution!