Replace LayoutStrategy buffered_bytes with a buffered bytes tracker

[robert3005]

For file writing it's very useful to know how much data is already piped through
the writer. We have a CountingWriter but that can only measure flushed bytes. We
want to measure the bytes that the writer holds buferred.

Instead of recursive buffered_bytes which has numerous problems with stateless
strategies and double counting we add a bufferedbytestracker to the
layoutwritercontext and let writers report buffered bytes there

[codspeed-hq]

Merging this PR will degrade performance by 10.99%

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

❌ 1 regressed benchmark
✅ 1883 untouched benchmarks
⏩ 12 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	fsl_large	88 µs	98.8 µs	-10.99%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing rk/notodobytes (aa8fd1c) with develop (81c36da)}

Footnotes

1. 12 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩