fix(npx): auto-approve installable fallbacks

[youbamj]

Summary

• add a shared npx_command() helper so install-capable fallback paths run npx -y ... consistently instead of plain npx ...
• update the ccusage, tsc, next, and prisma fallback paths to use the shared helper, while leaving npx --no-install call sites unchanged
• fix a first-run npx ccusage bug where interactive approval could block execution and make flows such as cargo test --all appear to hang or time out, and document the fix in CHANGELOG.md

Test plan

• cargo fmt --all && cargo clippy --all-targets && cargo test
• Unit test added for npx_command() to verify -y is always included
• Manual testing: ./target/debug/rtk cc-economics returns without timing out when ccusage is only available via npx
• Manual testing: ./target/debug/rtk cc-economics --daily returns without timing out when ccusage is only available via npx
• Manual testing: ./target/debug/rtk tsc -- --version returns without timing out through the npx fallback path
• Manual testing: ./target/debug/rtk next -- --help returns without timing out through the npx fallback path
• Manual testing: ./target/debug/rtk prisma generate returns without timing out through the npx fallback path and fails fast on missing schema instead of hanging
• Manual testing: ./target/debug/rtk npx prisma --version returns without timing out through the passthrough npx path
• Manual testing: ./target/release/rtk cc-economics returns without timing out when ccusage is only available via npx
• Manual testing: ./target/release/rtk cc-economics --daily returns without timing out when ccusage is only available via npx
• Manual testing: ./target/release/rtk tsc -- --version returns without timing out through the npx fallback path
• Manual testing: ./target/release/rtk next -- --help returns without timing out through the npx fallback path
• Manual testing: ./target/release/rtk prisma generate returns without timing out through the npx fallback path and fails fast on missing schema instead of hanging
• Manual testing: ./target/release/rtk npx prisma --version returns without timing out through the passthrough npx path

Closes #739

[CLAassistant]

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3 out of 4 committers have signed the CLA.

✅ youbamj
✅ aeppling
✅ Maimer
❌ apowis
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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