⚡ Bolt: [performance improvement]

[cloudesize67-cmd]

💡 What: Optimized string manipulations to avoid intermediate vector allocations. Replaced .collect::<Vec<_>>().join("") with .collect::<String>() and avoided .collect::<Vec<&str>>() before iterating over split strings. Also used character-based .split() instead of string-based.
🎯 Why: Creating temporary Vecs for strings only to immediately iterate or join them creates unnecessary heap allocations, hurting performance. Single-character string splits are also marginally slower than char-based splits.
📊 Impact: Reduces memory allocations and slightly improves execution speed during string processing in the generator.
🔬 Measurement: Verify by running make check and make test-generator. Memory profiles should show fewer allocations in these paths.

---

PR created automatically by Jules for task 6530942986378074351 started by @cloudesize67-cmd

[google-labs-jules]

👋 Jules, reporting for duty! I'm here to lend a hand with this pull request.

When you start a review, I'll add a 👀 emoji to each comment to let you know I've read it. I'll focus on feedback directed at me and will do my best to stay out of conversations between you and other bots or reviewers to keep the noise down.

I'll push a commit with your requested changes shortly after. Please note there might be a delay between these steps, but rest assured I'm on the job!

For more direct control, you can switch me to Reactive Mode. When this mode is on, I will only act on comments where you specifically mention me with @jules. You can find this option in the Pull Request section of your global Jules UI settings. You can always switch back!

New to Jules? Learn more at jules.google/docs.

---

For security, I will only act on instructions from the user who triggered this task.