7-Zip is a hard Windows prerequisite for west sdk install with no check anywhere

[alpCaner]

What

7-Zip is a hard prerequisite for west sdk install on native Windows, and it has no doctor check, no row, and no install action anywhere in the three repos. It exists only as one line of prose inside a tan bootstrap terminal transcript.

Source of the fact — alp-sdk/metadata/bootstrap.json manualInstallHints.windows.note[1]:

"7-Zip must already be on PATH before running west sdk install on native Windows: west delegates .7z extraction to patoolib, which shells out to an external 7z/7za/7zr/7zz/7zzs/unar binary and has no pure-Python fallback."

Rendered only by crates/tan-core/src/bootstrap/blocks.rs:155-164, under the heading "bootstrap: NOT auto-installed (manual, one-time):".

Customer-visible failure

west sdk install --version 1.0.1 -t arm-zephyr-eabi fails inside patoolib with an extraction error that names no Alp surface. Nothing connects that error back to 7-Zip.

A case-insensitive grep for 7z over alp-sdk-vscode/src returns nothing, so the IDE cannot surface it either.

Ask

Give it a real check in build_readiness so it can become a row with an install action, the way dtc and gperf already are. Nearest existing shape on the consumer side: alp-sdk-vscode/src/toolchain/vscodeAdapter.ts:86 dtc: probeTool("dtc", ["--version"]).

Depends on the same push_tool routing as the Zephyr SDK check.

[alpCaner]

Fixed on dev in #223 (squashed).

doctor --build now emits a sevenZip check with a runnable winget install -e --id 7zip.7zip, verified resolvable before being written down (winget show 7zip.7zip returned Found 7-Zip [7zip.7zip], publisher Igor Pavlov) rather than guessed — that file's own standing rule is that an invented command behind a Fix button is worse than null.

Two gates, both deliberate:

• Native Windows only — is_windows, not !is_linux; macOS is neither and needs no external extractor.
• Only while the SDK is still absent — the extractor is irrelevant once the toolchain is installed, so the row appears beside the zephyrSdk Fail it unblocks and disappears with it, instead of becoming a permanent warn for a tool nothing will use again.

The probe accepts any of 7z, 7za, 7zr, 7zz, 7zzs or unar — patoolib takes the first it finds, so probing only 7z would report a false negative on a host that has one of the others.

One thing this does NOT fix: the command is compiled into tan rather than read from the manifest, because 7-Zip is in no prerequisites.<os> list. Filed as alp-sdk#1036; the constant's doc comment names it, so there is a single thing to delete when that lands.