VarBinViewBuilder: support appending buffers directly into the builder storage

[robert3005]

throughout string encodings we have a repeated pattern that want to directly
write values to the varbinview builder without additional copy. This pr
generalizes this functionality

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[codspeed-hq]

Merging this PR will regress 5 benchmarks

⚠️ 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.

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 11 improved benchmarks
❌ 5 regressed benchmarks
✅ 1952 untouched benchmarks
⏩ 8 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	decompress[u32, (10000, 1024)]	78.5 µs	95.2 µs	-17.55%
❌	Simulation	fsst_decompress_string	7.2 ms	8.3 ms	-12.77%
❌	Simulation	decompress_fsst[(10000, 4, 4)]	794.2 µs	901 µs	-11.85%
❌	Simulation	decompress_fsst[(10000, 4, 8)]	815.5 µs	922.1 µs	-11.56%
❌	Simulation	canonicalize_compare[(10000, 4, 4)]	955.9 µs	1,064.1 µs	-10.17%
⚡	Simulation	chunked_varbin_to_varbinview_builder[(10, 100)]	509.3 µs	329.1 µs	+54.76%
⚡	Simulation	chunked_varbin_opt_to_varbinview_builder[(10, 100)]	794.1 µs	554.8 µs	+43.14%
⚡	Simulation	chunked_varbin_to_varbinview_builder[(500, 2)]	164.5 µs	119.1 µs	+38.13%
⚡	Simulation	chunked_varbin_into_canonical[(10, 100)]	670.9 µs	488 µs	+37.47%
⚡	Simulation	chunked_varbin_into_canonical[(500, 2)]	175.4 µs	130.9 µs	+33.94%
⚡	Simulation	chunked_varbin_opt_to_varbinview_builder[(500, 2)]	162.4 µs	122.5 µs	+32.57%
⚡	Simulation	chunked_into_canonical[(1000, 50, 8, 4)]	17.9 ms	15.7 ms	+14.22%
⚡	Simulation	chunked_canonicalize_into[(1000, 50, 8, 4)]	15.1 ms	13.2 ms	+13.66%
⚡	Simulation	chunked_canonicalize_into[(1000, 50, 8, 16)]	16.2 ms	14.3 ms	+12.98%
⚡	Simulation	chunked_into_canonical[(1000, 50, 8, 16)]	19 ms	16.8 ms	+12.83%
⚡	Simulation	decompress[u64, (1000, 16)]	73 µs	65.2 µs	+11.87%

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/varbinview-append-buffer (a0bec35) with develop (a1057db)}

Footnotes

1. 8 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. ↩