chore: polish cuDF C FFI

[0ax1]

Add vx_cuda_session_new so C FFI callers can create a CUDA-enabled Vortex session once and reuse it across Arrow Device exports.

Document the CUDA export sync_event lifetime and guard the Arrow C Device definitions in vortex_cuda.h with ARROW_C_DEVICE_DATA_INTERFACE, preserving USE_OWN_ARROW_DEVICE as an opt-out.

[0ax1]

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[codspeed-hq]

Merging this PR will degrade performance by 19.45%

⚠️ 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.

⚡ 6 improved benchmarks
❌ 106 regressed benchmarks
✅ 1416 untouched benchmarks
⏩ 10 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	compare[48]	213 µs	300.7 µs	-29.16%
❌	Simulation	compare[50]	227.7 µs	319.2 µs	-28.65%
❌	Simulation	compare[49]	228.2 µs	317.7 µs	-28.19%
❌	Simulation	compare[44]	207.5 µs	287.7 µs	-27.88%
❌	Simulation	compare[46]	218.5 µs	302.5 µs	-27.76%
❌	Simulation	compare[47]	223.5 µs	309.4 µs	-27.75%
❌	Simulation	compare[40]	190.7 µs	263.5 µs	-27.64%
❌	Simulation	compare[44]	212.2 µs	292.4 µs	-27.43%
❌	Simulation	compare[45]	218.9 µs	301 µs	-27.28%
❌	Simulation	compare[43]	209.2 µs	287.7 µs	-27.26%
❌	Simulation	compare[42]	204.6 µs	281.1 µs	-27.22%
❌	Simulation	compare[40]	195.6 µs	268.4 µs	-27.1%
❌	Simulation	compare[43]	214.2 µs	292.6 µs	-26.79%
❌	Simulation	compare[42]	209.4 µs	285.9 µs	-26.76%
❌	Simulation	compare[41]	204.5 µs	279.2 µs	-26.74%
❌	Simulation	compare[41]	209.3 µs	284 µs	-26.29%
❌	Simulation	compare[39]	199.9 µs	270.8 µs	-26.19%
❌	Simulation	compare[31]	157.7 µs	213.7 µs	-26.19%
❌	Simulation	compare[38]	195.5 µs	264.6 µs	-26.11%
❌	Simulation	compare[36]	187.3 µs	252.6 µs	-25.87%
...	...	...	...	...	...

ℹ️ Only the first 20 benchmarks are displayed. Go to the app to view all benchmarks.

Tip

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

---

_{Comparing perf/cudf-ffi-session-header (98f5bbb) with develop (3731d5b)}

Footnotes

1. 10 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. ↩

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