CI: Default BOOTSTRAP_M3_HELLOWORLD_STRICT_GATE=1 in ci-local after #1493

[PurHur]

Milestone

M3 (HelloWorld strict CI) — parent #1492. CI flip only; probe green.

Problem

BOOTSTRAP_M3_HELLOWORLD_STRICT_GATE remains opt-in in ci-local.sh while make bootstrap-selfhost-helloworld is strict-by-default and green with emit_path=native.

Harness status (2026-05-28)

./script/docker-exec.sh -- bash -lc 'make bootstrap-selfhost-helloworld'
# bootstrap-selfhost-helloworld-probe: OK emit_path=native

Scope

File	Change
script/ci-defaults.env	BOOTSTRAP_M3_HELLOWORLD_STRICT_GATE=1
script/ci-common.sh	Existing hook — no probe rewrite
docs/local-ci-matrix.md	Opt-out =0

Repro

./script/docker-exec.sh -- bash -lc 'make bootstrap-selfhost-helloworld'

Done when

• Default ci-local.sh runs HelloWorld strict when LLVM present
• Opt-out documented

Links

#1492 · #1526 · #2165 (sibling)