Further updates to Agent

kernel/bin/agent

@@ -558,6 +558,91 @@ function bareEditCreateStdinReader(stdin) {
   }
 }
 
+/** Minimal AbortController for Bare/Pear when globalThis lacks it (drive-resident /bin preamble). */
+
+function bareAgentEnsureAbortPolyfill() {
+  const g =
+    typeof globalThis !== 'undefined'
+      ? globalThis
+      : typeof global !== 'undefined'
+        ? global
+        : typeof self !== 'undefined'
+          ? self
+          : /** @type {Record<string, unknown>} */ ({})
+  if (typeof g.AbortController === 'function') return
+
+  function BareAbortSignal() {
+    /** @type {boolean} */
+    this.aborted = false
+    /** @type {unknown} */
+    this.reason = undefined
+    /** @type {{ fn: () => void, once: boolean }[]} */
+    this._listeners = []
+  }
+
+  BareAbortSignal.prototype.addEventListener = function (type, fn, opts) {
+    if (type !== 'abort' || typeof fn !== 'function') return
+    const once = !!(opts && opts.once)
+    if (this.aborted) {
+      if (once) {
+        try {
+          fn.call(this)
+        } catch {
+          /* ignore */
+        }
+      }
+      return
+    }
+    this._listeners.push({ fn: /** @type {() => void} */ (fn), once })
+  }
+
+  BareAbortSignal.prototype.removeEventListener = function (type, fn) {
+    if (type !== 'abort' || typeof fn !== 'function') return
+    this._listeners = this._listeners.filter((x) => x.fn !== fn)
+  }
+
+  BareAbortSignal.prototype.throwIfAborted = function () {
+    if (!this.aborted) return
+    const DOMException = g.DOMException
+    if (typeof DOMException === 'function') {
+      throw new DOMException('Aborted', 'AbortError')
+    }
+    const e = new Error('Aborted')
+    e.name = 'AbortError'
+    throw e
+  }
+
+  function BareAbortController() {
+    this.signal = new BareAbortSignal()
+  }
+
+  BareAbortController.prototype.abort = function (reason) {
+    const s = this.signal
+    if (s.aborted) return
+    s.aborted = true
+    s.reason = reason
+    const list = s._listeners.slice()
+    s._listeners.length = 0
+    for (const x of list) {
+      try {
+        x.fn.call(s)
+      } catch {
+        /* ignore */
+      }
+    }
+  }
+
+  if (typeof globalThis !== 'undefined') {
+    globalThis.AbortController = BareAbortController
+    globalThis.AbortSignal = BareAbortSignal
+  } else {
+    g.AbortController = BareAbortController
+    g.AbortSignal = BareAbortSignal
+  }
+}
+
+bareAgentEnsureAbortPolyfill()
+
 /** ~/.agent paths, config, history trim, man digest (preamble for /bin/agent). */
 
 /**