chore: release 0.3.0 with idx-mcp

Bump the workspace and npm packages to 0.3.0. The release workflow
builds and attaches idx-mcp binaries next to idx, the npm launcher and
installer pick their binary from package.json so npm/idx-mcp reuses
them, and the npm smoke test covers both packages.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

scripts/npm-smoke.sh

@@ -3,7 +3,6 @@ set -Eeuo pipefail
 
 repo_root="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
 smoke_dir="$(mktemp -d "${TMPDIR:-/tmp}/idx-cli-npm-smoke.XXXXXX")"
-install_dir="${smoke_dir}/install"
 npm_cache="${smoke_dir}/npm-cache"
 
 cleanup() {
@@ -21,54 +20,64 @@ trap on_error ERR
 
 cd "$repo_root"
 
-release_binary="${repo_root}/target/release/idx"
-if [[ -x "$release_binary" ]]; then
-  echo "npm smoke: reusing ${release_binary}"
+# Packs the npm package in <dir>, installs it with the local release binary,
+# and checks that `<bin> --help` prints `<usage>`.
+smoke_package() {
+  local package_dir="$1" bin="$2" usage="$3"
+  local release_binary="${repo_root}/target/release/${bin}"
+  local work="${smoke_dir}/${bin}"
+  local install_dir="${work}/install"
+  mkdir -p "$work" "$install_dir"
+
+  if [[ ! -x "$release_binary" ]]; then
+    echo "npm smoke: release binary was not produced at ${release_binary}" >&2
+    exit 1
+  fi
+
+  echo "npm smoke: packing ${package_dir}"
+  local tarball_name tarball
+  tarball_name="$(cd "$package_dir" && npm_config_cache="$npm_cache" npm pack --silent --pack-destination "$work" | tail -n 1)"
+  tarball="${work}/${tarball_name}"
+  if [[ -z "$tarball_name" || ! -f "$tarball" ]]; then
+    echo "npm smoke: expected tarball was not produced at ${tarball}" >&2
+    exit 1
+  fi
+
+  local binary_url
+  binary_url="$(node -e 'const { pathToFileURL } = require("node:url"); process.stdout.write(pathToFileURL(process.argv[1]).href)' "$release_binary")"
+  echo "npm smoke: installing ${tarball_name} into ${install_dir}"
+  npm_config_cache="$npm_cache" IDX_BINARY_URL="$binary_url" npm install \
+    --prefix "$install_dir" \
+    "$tarball" \
+    --no-save \
+    --no-package-lock \
+    --no-audit \
+    --no-fund \
+    --foreground-scripts
+
+  local resolved_bin="${install_dir}/node_modules/.bin/${bin}"
+  if [[ ! -x "$resolved_bin" ]]; then
+    echo "npm smoke: npm did not create an executable bin link at ${resolved_bin}" >&2
+    exit 1
+  fi
+
+  echo "npm smoke: running installed ${bin} --help"
+  "$resolved_bin" --help | tee "${work}/help.txt"
+  if ! grep -q "$usage" "${work}/help.txt"; then
+    echo "npm smoke: ${bin} --help did not contain '${usage}'" >&2
+    exit 1
+  fi
+}
+
+if [[ -x target/release/idx && -x target/release/idx-mcp ]]; then
+  echo "npm smoke: reusing target/release/{idx,idx-mcp}"
 else
-  echo "npm smoke: building ${release_binary}"
-  cargo build --release --locked
+  echo "npm smoke: building release binaries"
+  cargo build --release --locked -p idx-cli -p idx-mcp
 fi
 
-if [[ ! -x "$release_binary" ]]; then
-  echo "npm smoke: release binary was not produced at ${release_binary}" >&2
-  exit 1
-fi
-
-echo "npm smoke: packing wrapper"
 mkdir -p "$npm_cache"
-tarball_name="$(npm_config_cache="$npm_cache" npm pack --silent --pack-destination "$smoke_dir" | tail -n 1)"
-tarball="${smoke_dir}/${tarball_name}"
-if [[ -z "$tarball_name" || ! -f "$tarball" ]]; then
-  echo "npm smoke: expected tarball was not produced at ${tarball}" >&2
-  exit 1
-fi
-
-mkdir -p "$install_dir"
-binary_url="$(node -e 'const { pathToFileURL } = require("node:url"); process.stdout.write(pathToFileURL(process.argv[1]).href)' "$release_binary")"
-echo "npm smoke: installing tarball into ${install_dir}"
-npm_config_cache="$npm_cache" IDX_BINARY_URL="$binary_url" npm install \
-  --prefix "$install_dir" \
-  "$tarball" \
-  --no-save \
-  --no-package-lock \
-  --no-audit \
-  --no-fund \
-  --foreground-scripts
-
-resolved_bin="${install_dir}/node_modules/.bin/idx"
-if [[ ! -x "$resolved_bin" ]]; then
-  echo "npm smoke: npm did not create an executable bin link at ${resolved_bin}" >&2
-  exit 1
-fi
-
-help_output="${smoke_dir}/help.txt"
-echo "npm smoke: running installed idx --help"
-"$resolved_bin" --help | tee "$help_output"
-if ! grep -q "Usage: idx" "$help_output"; then
-  echo "npm smoke: --help output did not contain the expected usage line" >&2
-  exit 1
-fi
-
-echo "npm smoke: running installed idx config --help"
-"$resolved_bin" config --help
-echo "npm smoke: PASS (pack, install, --help, and config --help)"
+smoke_package "$repo_root" idx "Usage: idx"
+"${smoke_dir}/idx/install/node_modules/.bin/idx" config --help >/dev/null
+smoke_package "${repo_root}/npm/idx-mcp" idx-mcp "Usage: idx-mcp"
+echo "npm smoke: PASS (idx-cli and idx-mcp: pack, install, --help)"