feat: Hooks (#9093)

examples/plugins/hello-hooks/scripts/announce.sh

@@ -0,0 +1,36 @@
+#!/usr/bin/env bash
+# Tiny hook handler that loudly announces every event goose fires at it.
+#
+# Goose pipes the event payload as JSON on stdin and sets PLUGIN_ROOT in the
+# environment. We tee a copy of the payload into a log file inside the plugin
+# directory so you can see the full structure later.
+set -euo pipefail
+
+label="${1:-event}"
+log="${PLUGIN_ROOT:-.}/last-event.log"
+payload="$(cat)"
+
+event_name="$(printf '%s' "$payload" | sed -n 's/.*"event":"\([^"]*\)".*/\1/p')"
+tool_name="$(printf '%s' "$payload" | sed -n 's/.*"tool_name":"\([^"]*\)".*/\1/p')"
+
+emoji() {
+  case "$1" in
+    start)     printf '\xf0\x9f\x9a\x80' ;;  # rocket
+    prompt)    printf '\xf0\x9f\x92\xac' ;;  # speech balloon
+    pre-tool)  printf '\xe2\x9a\xa1' ;;      # zap
+    post-tool) printf '\xe2\x9c\x85' ;;      # check
+    *)         printf '\xf0\x9f\x94\x94' ;;  # bell
+  esac
+}
+
+icon="$(emoji "$label")"
+suffix=""
+[ -n "$tool_name" ] && suffix=" tool=$tool_name"
+
+# Both stderr (so it shows up alongside goose tracing) and a log file.
+printf '%s [hello-hooks] %s%s\n' "$icon" "${event_name:-$label}" "$suffix" 1>&2
+
+{
+  printf -- '---- %s @ %s ----\n' "${event_name:-$label}" "$(date -u '+%Y-%m-%dT%H:%M:%SZ')"
+  printf '%s\n' "$payload"
+} >> "$log"