add deno git precommit hook

Author: landsman

.hooks/pre-commit

@@ -0,0 +1,5 @@
+#!/usr/bin/env sh
+. "$(dirname -- "$0")/_/hook.sh"
+
+deno fmt --check supabase/*
+deno lint supabase/*

deno.json

@@ -0,0 +1,5 @@
+{
+  "tasks": {
+    "hook": "deno run --allow-read --allow-run --allow-write https://deno.land/x/[email protected]/mod.ts"
+  }
+}