Fix bin/publish: copy docs.dist from project root

Fix bin/publish: use correct .env path for rspade_system
Fix bin/publish script: prevent grep exit code 1 from terminating script

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

node_modules/fs-extra/lib/path-exists/index.js

@@ -0,0 +1,12 @@
+'use strict'
+const u = require('universalify').fromPromise
+const fs = require('../fs')
+
+function pathExists (path) {
+  return fs.access(path).then(() => true).catch(() => false)
+}
+
+module.exports = {
+  pathExists: u(pathExists),
+  pathExistsSync: fs.existsSync
+}