feat(install): add SENTRY_INIT env var to run wizard after install

Lets users install the CLI and launch the setup wizard in one command:

    curl -fsSL https://cli.sentry.dev/install | SENTRY_INIT=1 bash

After the normal install completes, resolves the installed binary path
and runs `sentry init </dev/tty`. The </dev/tty reopens stdin from
the terminal since `curl | bash` consumes it for the pipe.

Also adds `install` to the docs-preview workflow path filter so changes
to the install script trigger a preview build.

Closes #682

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: betegon

.github/workflows/docs-preview.yml

@@ -4,6 +4,7 @@ on:
   pull_request:
     paths:
       - 'docs/**'
+      - 'install'
       - '.github/workflows/docs-preview.yml'
 
 permissions:

install

@@ -89,9 +89,11 @@ Options:
 Environment Variables:
     SENTRY_INSTALL_DIR      Override the installation directory
     SENTRY_VERSION          Install a specific version (e.g., 0.19.0, nightly)
+    SENTRY_INIT             Set to 1 to run \`sentry init\` after installing
 
 Examples:
     curl -fsSL https://cli.sentry.dev/install | bash
+    curl -fsSL https://cli.sentry.dev/install | SENTRY_INIT=1 bash
     curl -fsSL https://cli.sentry.dev/install | bash -s -- --version nightly
     curl -fsSL https://cli.sentry.dev/install | bash -s -- --version 0.19.0
     SENTRY_VERSION=nightly curl -fsSL https://cli.sentry.dev/install | bash
@@ -276,3 +278,21 @@ trap - EXIT
 
 # shellcheck disable=SC2086
 "$tmp_binary" cli setup $setup_args
+
+# Optionally launch the setup wizard after install.
+# Resolve the installed binary path using the same logic as the TS code:
+# SENTRY_INSTALL_DIR > ~/.local/bin > ~/bin > ~/.sentry/bin
+# </dev/tty reopens stdin from the terminal since `curl | bash` consumes it.
+if [[ "${SENTRY_INIT:-}" == "1" ]]; then
+  sentry_bin=""
+  for dir in "${SENTRY_INSTALL_DIR:-}" "$HOME/.local/bin" "$HOME/bin" "$HOME/.sentry/bin"; do
+    if [[ -x "${dir}/sentry" ]]; then
+      sentry_bin="${dir}/sentry"
+      break
+    fi
+  done
+  if [[ -z "$sentry_bin" ]]; then
+    die "Cannot find installed sentry binary" "init"
+  fi
+  "$sentry_bin" init </dev/tty
+fi