feat(pi): add agent integration

[YHM404]

Summary

• add a thin pi extension that overrides pi's bash tool and delegates to rtk rewrite
• add rtk init -g --agent pi install, uninstall, and config-status support
• document pi in the supported tools list and installation examples

Test plan

• cargo fmt --all --check && cargo clippy --all-targets && cargo test
• Manual testing: installed the extension in pi, ran /reload, and verified git status was rewritten to RTK output

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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

[snitramodranoel]

Should be closed in favor of #1741