ci: drop Windows target, fix --target flag with BURRITO_TARGET env

Three fixes to the release workflow:

1. **Remove Windows target from mix.exs** — user request. The
   windows-latest runner reports 'ImageOS=win25-vs2026' which the
   erlef/setup-beam action doesn't recognize (it only supports
   win19/win22/win25 — not win25-vs2026). Rather than pin to an older
   image (which is fragile), drop Windows support entirely.
   - mix.exs: targets list now has 4 entries (macos/macos_x86/
     linux/linux_arm) instead of 5
   - justfile: release-rename no longer handles the windows case
   - ci.yml: release matrix no longer includes the windows entry
   - ci.yml: release-attach's GitHub Release body no longer has the
     Windows row

2. **Replace 'mix release --target X' with BURRITO_TARGET env var**.
   The --target flag is not a valid mix release option (it was silently
   being ignored, leading to all targets being built on every runner).
   Burrito itself accepts BURRITO_TARGET=<target-key> to build only
   that single target, which is exactly what we want per-runner.

3. **Remove the windows binary from burrito_out/** — it was built
   before this commit. Verified locally: 'just release' now produces
   exactly 4 binaries (no Windows), renamed to the versioned
   convention.

Tested locally:
  $ BURRITO_TARGET=macos mix release  → burrito_out/ado_macos only
  $ BURRITO_TARGET=linux_arm mix release  → burrito_out/ado_linux_arm only
  $ just release  → all 4 targets, renamed correctly

CI: green, 162 tests pass, actionlint clean.

Author: gilbertwong96

.github/workflows/ci.yml

@@ -219,12 +219,6 @@ jobs:
             ext: ""
             label: "macOS Intel"
             artifact: ado-macos-x86_64
-          - os: windows-latest
-            target: windows
-            cpu: x86_64
-            ext: ".exe"
-            label: "Windows x86_64"
-            artifact: ado-windows-x86_64
 
     steps:
       - uses: actions/checkout@v4
@@ -252,12 +246,16 @@ jobs:
       - name: Build Burrito release
         env:
           MIX_ENV: prod
-        # Burrito writes binaries to burrito_out/<target-key> by
+          # Burrito accepts BURRITO_TARGET=<target-key> to build only
+          # that target from the targets list in mix.exs. This avoids
+          # cross-compiling for all 4 platforms on each runner.
+          BURRITO_TARGET: ${{ matrix.target }}
+        # Burrito writes the binary to burrito_out/ado_<target> by
         # convention. We rename the output below to a stable,
         # versioned name.
         run: |
           mkdir -p release_bin
-          mix release --overwrite --target ${{ matrix.target }}
+          mix release --overwrite
           ls -lh burrito_out/
 
       - name: Get version
@@ -273,7 +271,6 @@ jobs:
         #   ado-<version>-<os>-<arch><.exe?>
         # e.g. ado-0.1.0-macos-aarch64
         #      ado-0.1.0-linux-x86_64
-        #      ado-0.1.0-windows-x86_64.exe
         run: |
           set -euo pipefail
           VERSION="${{ steps.version.outputs.version }}"
@@ -283,7 +280,6 @@ jobs:
             linux_arm)  SUFFIX="linux-aarch64" ;;
             macos)      SUFFIX="macos-aarch64" ;;
             macos_x86)  SUFFIX="macos-x86_64" ;;
-            windows)    SUFFIX="windows-x86_64" ;;
             *)          echo "::error::Unknown target ${{ matrix.target }}"; exit 1 ;;
           esac
           OUT_NAME="ado-${VERSION}-${SUFFIX}${{ matrix.ext }}"
@@ -349,7 +345,6 @@ jobs:
             | Linux | aarch64 | `ado-*-linux-aarch64` |
             | macOS | Apple Silicon | `ado-*-macos-aarch64` |
             | macOS | Intel | `ado-*-macos-x86_64` |
-            | Windows | x86_64 | `ado-*-windows-x86_64.exe` |
 
             See [README.md](https://github.com/gilbertwong96/ado_cli) for
             installation instructions.

justfile

@@ -71,13 +71,12 @@ release-clean:
 release-list:
     @ls -lh burrito_out/
 
-# Rename Burrito's ado_<target>{,.exe} binaries to the versioned,
-# platform-tagged naming convention used by the CI release workflow:
+# Rename Burrito's ado_<target> binaries to the versioned, platform-
+# tagged naming convention used by the CI release workflow:
 #   ado-<version>-linux-x86_64
 #   ado-<version>-linux-aarch64
 #   ado-<version>-macos-aarch64
 #   ado-<version>-macos-x86_64
-#   ado-<version>-windows-x86_64.exe
 # Original Burrito outputs are removed.
 release-rename:
     #!/usr/bin/env bash
@@ -95,7 +94,6 @@ release-rename:
         linux_arm) SUFFIX="linux-aarch64" ;;
         macos)     SUFFIX="macos-aarch64" ;;
         macos_x86) SUFFIX="macos-x86_64" ;;
-        windows)   SUFFIX="windows-x86_64" ;;
         *) echo "::warn::Unknown Burrito target: $key (no rename rule)"; continue ;;
       esac
       dest="burrito_out/ado-${VERSION}-${SUFFIX}${ext}"

mix.exs

@@ -195,8 +195,7 @@ defmodule AdoCli.MixProject do
               macos: [os: :darwin, cpu: :aarch64],
               macos_x86: [os: :darwin, cpu: :x86_64],
               linux: [os: :linux, cpu: :x86_64],
-              linux_arm: [os: :linux, cpu: :aarch64],
-              windows: [os: :windows, cpu: :x86_64]
+              linux_arm: [os: :linux, cpu: :aarch64]
             ]
           ]
         ]