ci: make CI genuinely green — rust-ci toolchain pin + canonical Julia… #15

	# SPDX-License-Identifier: MPL-2.0
	# abi-ffi-gate.yml — enforce that the Zig FFI conforms to the Idris2 ABI.
	#
	# The Idris2 ABI (src/interface/abi) is the source of truth. This gate fails if
	# the Zig FFI (src/interface/ffi) drifts from it: a declared C function with no
	# export, a mismatched result-code map, or an unrendered template token. A
	# second job builds + tests the Zig FFI under the pinned Zig 0.14.0.
	name: ABI-FFI Gate

	on:
	pull_request:
	push:
	branches: [main, master]

	permissions:
	contents: read

	jobs:
	conformance:
	name: ABI ↔ FFI structural conformance
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- name: Install Julia 1.11.5
	run: \|
	curl -fsSL https://julialang-s3.julialang.org/bin/linux/x64/1.11/julia-1.11.5-linux-x86_64.tar.gz -o /tmp/julia.tar.gz
	tar -xf /tmp/julia.tar.gz -C /tmp
	echo "/tmp/julia-1.11.5/bin" >> "$GITHUB_PATH"
	- name: Run ABI-FFI gate
	run: \|
	julia --version # confirms the pinned 1.11.5 is on PATH, not the runner default
	julia scripts/abi-ffi-gate.jl

	zig-build:
	name: Zig FFI builds + tests (Zig 0.14.0)
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- name: Install Zig 0.14.0
	run: \|
	curl -fsSL https://ziglang.org/download/0.14.0/zig-linux-x86_64-0.14.0.tar.xz -o /tmp/zig.tar.xz
	tar -xf /tmp/zig.tar.xz -C /tmp
	echo "/tmp/zig-linux-x86_64-0.14.0" >> "$GITHUB_PATH"
	- name: zig test FFI
	run: zig test src/interface/ffi/src/main.zig -lc

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