⚡ Bolt: Remove push_str(&format!(...)) allocations

[Tcode-Motion]

💡 What: Replaced inefficient push_str(&format!(...)) calls with write!(...) directly onto string buffers across several Rust modules. Imported std::fmt::Write trait where necessary.
🎯 Why: The push_str(&format!(...)) anti-pattern allocates an intermediate String internally on each iteration, causing significant overhead in formatting strings, especially when done in loops (like diagnostic generation, documentation rendering, and bytecode tracing). Writing directly to the buffer bypasses this intermediate heap allocation completely.
📊 Impact: Reduces redundant string allocations across the compiler CLI, runtime built-ins, bytecode disassembler, and debugger.
🔬 Measurement: Benchmarks focusing on the diagnostics rendering and trace execution paths should reflect reduced peak memory consumption and slightly faster execution speeds. This optimization is easily testable via cargo test --workspace ensuring zero behavioral regressions.

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PR created automatically by Jules for task 3653897259569321771 started by @Tcode-Motion

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