fix(cli): ensure blocking stdio

[wan9chi]

Summary

• clear inherited O_NONBLOCK from non-TTY stdin, stdout, and stderr at process entry
• call the helper from the global Rust CLI and once from the local NAPI entry
• update the E2E snapshots from the normalized truncation failure to all 1,282 output lines, including the final 128-warning summary

Root cause

Node marks non-TTY stdio as non-blocking, and the flag is shared with inherited child descriptors. Rust's standard I/O and embedded dependencies assume blocking writes, so a full consumer pipe can return EAGAIN, truncate diagnostics, or panic.

This PR is intentionally scoped to restoring blocking stdio. It does not add write-site retries or io::Result propagation.

Fixes #2165.

Validation

• cargo test -p vite_shared clears_nonblocking_from_a_non_tty_file_description
• pnpm -F vite-plus build
• just snapshot-test check_backpressure (local and global; repeated compare-mode runs)
• just check
• just lint
• just test
• git diff --check

Stack: 2 of 2. Depends on #2172.

[wan9chi]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
Learn more

• fix(cli): ensure blocking stdio #2173 👈 (View in Graphite)
• test(cli): reproduce stdio backpressure #2172
• main

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[github-actions]

Native binary sizes (82821df)

Final release artifacts built by the canonical build-upstream and build-windows-cli actions.

Artifact	Format	Base	PR	Change
vp (Linux x64)	Binary	10.32 MiB	10.32 MiB	0 B (0.00%)
vp (Linux x64)	gzip -9	4.42 MiB	4.42 MiB	+476 B (+0.01%)
NAPI (Linux x64)	Binary	33.42 MiB	33.42 MiB	0 B (0.00%)
NAPI (Linux x64)	gzip -9	12.78 MiB	12.78 MiB	+502 B (+0.00%)
vp (macOS ARM64)	Binary	7.64 MiB	7.65 MiB	+16.13 KiB (+0.21%)
vp (macOS ARM64)	gzip -9	3.83 MiB	3.83 MiB	+333 B (+0.01%)
NAPI (macOS ARM64)	Binary	40.78 MiB	40.78 MiB	0 B (0.00%)
NAPI (macOS ARM64)	gzip -9	17.05 MiB	17.05 MiB	-225 B (-0.00%)
vp (Windows x64)	Binary	8.37 MiB	8.37 MiB	0 B (0.00%)
vp (Windows x64)	gzip -9	3.64 MiB	3.64 MiB	+1 B (+0.00%)
NAPI (Windows x64)	Binary	27.88 MiB	27.88 MiB	+512 B (+0.00%)
NAPI (Windows x64)	gzip -9	10.78 MiB	10.78 MiB	+20 B (+0.00%)
Trampoline (Windows x64)	Binary	203.00 KiB	203.00 KiB	0 B (0.00%)
Trampoline (Windows x64)	gzip -9	97.91 KiB	97.91 KiB	0 B (0.00%)
Installer (Windows x64)	Binary	4.46 MiB	4.46 MiB	0 B (0.00%)
Installer (Windows x64)	gzip -9	2.08 MiB	2.08 MiB	0 B (0.00%)