feat(ai-quick-ask): add cj/gptel-quick-ask one-shot command

New module `modules/ai-quick-ask.el`.  Bound to `C-; a q` via
`cj/ai-keymap` ("quick ask").

`cj/gptel-quick-ask` reads a prompt in the minibuffer, creates a
transient `*GPTel-Quick*` buffer in `cj/gptel-quick-mode` (a
special-mode derivative with `q` / `escape` / `c` bindings), inserts
"Q: <prompt>" plus a response marker, then calls `gptel-request`
with `:stream t` so the answer streams into the buffer.  Doesn't
touch `*AI-Assistant*`, doesn't autosave.

Two follow-up commands work in the buffer:

- `cj/gptel-quick-dismiss` (`q` / `escape`): delete the window and
  kill the buffer.  Idempotent when the buffer is absent.
- `cj/gptel-quick-continue` (`c`): extract the prompt + response,
  seed them into `*AI-Assistant*` under proper org headings (matching
  the `cj/gptel--fresh-org-prefix` shape), display the side window,
  then dismiss the quick buffer.

13 tests cover the pure helpers (initial-text shape, response
extraction across normal / multi-line / no-marker / empty inputs,
seed-text shape), the ask path (buffer created in right mode,
prompt recorded, gptel-request called, empty-prompt error), the
dismiss path (kills buffer / no-op when absent), and the continue
path (seeds `*AI-Assistant*`, dismisses quick buffer, errors
outside a quick buffer).  `gptel-request` is stubbed in tests so
nothing hits the network.

2 files changed, 136 insertions, 0 deletions

diff --git a/modules/ai-config.el b/modules/ai-config.el
index e7907e36..6eff1ba6 100644
--- a/modules/ai-config.el
+++ b/modules/ai-config.el
@@ -34,6 +34,7 @@
 (autoload 'cj/gptel-load-conversation "ai-conversations" "Load a saved AI conversation." t)
 (autoload 'cj/gptel-delete-conversation "ai-conversations" "Delete a saved AI conversation." t)
 (autoload 'cj/gptel-autosave-toggle "ai-conversations" "Toggle autosave in the current GPTel buffer." t)
+(autoload 'cj/gptel-quick-ask "ai-quick-ask" "One-shot quick-ask in a transient buffer." t)
 
 ;;; ------------------------- AI Config Helper Functions ------------------------
 
@@ -508,6 +509,7 @@ Works for any buffer, whether it's visiting a file or not."
   "l" #'cj/gptel-load-conversation   ;; load and continue conversation
   "m" #'cj/gptel-change-model        ;; change the LLM model
   "p" #'gptel-system-prompt          ;; change prompt
+  "q" #'cj/gptel-quick-ask           ;; one-shot quick ask
   "r" #'gptel-rewrite                ;; rewrite a region of code/text
   "c" #'cj/gptel-context-clear       ;; clear all context
   "s" #'cj/gptel-save-conversation   ;; save conversation
@@ -527,6 +529,7 @@ Works for any buffer, whether it's visiting a file or not."
     "C-; a l" "load conversation"
     "C-; a m" "change model"
     "C-; a p" "change prompt"
+    "C-; a q" "quick ask"
     "C-; a r" "rewrite region"
     "C-; a c" "clear context"
     "C-; a s" "save conversation"
diff --git a/modules/ai-quick-ask.el b/modules/ai-quick-ask.el
new file mode 100644
index 00000000..0d56be8c
--- /dev/null
+++ b/modules/ai-quick-ask.el
@@ -0,0 +1,133 @@
+;;; ai-quick-ask.el --- One-shot GPTel quick-ask -*- lexical-binding: t; coding: utf-8; -*-
+
+;; Author: Craig Jennings <c@cjennings.net>
+
+;;; Commentary:
+;; Provides `cj/gptel-quick-ask': read a single prompt in the
+;; minibuffer, stream the response into a transient *GPTel-Quick*
+;; buffer.  The transient buffer is dismissible with q or escape and
+;; can be escalated with c into a full *AI-Assistant* conversation
+;; seeded with the prompt + response.
+;;
+;; Designed for impromptu help where the conversation thread doesn't
+;; matter.  Doesn't touch the *AI-Assistant* side window unless the
+;; user explicitly escalates, doesn't autosave anywhere.
+
+;;; Code:
+
+(defvar-local cj/gptel-quick--prompt nil
+  "Buffer-local: the prompt used for the current *GPTel-Quick* session.")
+
+(defconst cj/gptel-quick--buffer-name "*GPTel-Quick*"
+  "Buffer used for one-shot quick-ask Q&A.")
+
+(defconst cj/gptel-quick--response-marker "A: "
+  "String inserted before the response in the quick-ask buffer.")
+
+(defvar-keymap cj/gptel-quick-mode-map
+  :doc "Keymap for `cj/gptel-quick-mode'."
+  "q"        #'cj/gptel-quick-dismiss
+  "<escape>" #'cj/gptel-quick-dismiss
+  "c"        #'cj/gptel-quick-continue)
+
+(define-derived-mode cj/gptel-quick-mode special-mode "GPTel-Quick"
+  "Major mode for the one-shot *GPTel-Quick* buffer."
+  ;; Allow gptel-request to stream into the buffer despite the
+  ;; special-mode read-only default.
+  (setq-local buffer-read-only nil))
+
+(defun cj/gptel-quick--initial-text (prompt)
+  "Return the initial buffer body for a quick-ask of PROMPT.
+The result is \"Q: <prompt>\\n\\nA: \", with the response marker at
+the end so the streamed response lands right after it."
+  (format "Q: %s\n\n%s" prompt cj/gptel-quick--response-marker))
+
+(defun cj/gptel-quick--extract-response (text)
+  "Return the response portion of TEXT, or nil if not found.
+TEXT is the contents of a *GPTel-Quick* buffer.  The response is
+everything after the first occurrence of `cj/gptel-quick--response-marker'
+on its own line.  Returns nil when the marker is absent."
+  (when (string-match
+         (concat "^" (regexp-quote cj/gptel-quick--response-marker))
+         text)
+    (substring text (match-end 0))))
+
+(defun cj/gptel-quick--seed-text (prompt response)
+  "Format a *AI-Assistant* seed from PROMPT and RESPONSE.
+Matches the org-heading shape that `cj/gptel--fresh-org-prefix' and
+`cj/gptel-insert-model-heading' produce: a user heading followed by
+the prompt body, followed by an AI heading followed by the response."
+  (let ((ts (format-time-string "[%Y-%m-%d %H:%M:%S]")))
+    (format "* %s %s\n%s\n\n* AI %s\n%s\n"
+            user-login-name ts prompt
+            ts (or response ""))))
+
+;;;###autoload
+(defun cj/gptel-quick-ask (prompt)
+  "Read a one-shot PROMPT in the minibuffer and stream the answer.
+The response lands in a transient *GPTel-Quick* buffer.  Press q or
+escape to dismiss, or c to escalate into a full *AI-Assistant*
+conversation seeded with the prompt and response."
+  (interactive (list (read-string "Quick ask: ")))
+  (when (string-empty-p prompt)
+    (user-error "Empty prompt"))
+  (let ((buf (get-buffer-create cj/gptel-quick--buffer-name)))
+    (with-current-buffer buf
+      (cj/gptel-quick-mode)
+      (let ((inhibit-read-only t))
+        (erase-buffer)
+        (insert (cj/gptel-quick--initial-text prompt))
+        (setq-local cj/gptel-quick--prompt prompt)))
+    (unless (featurep 'gptel)
+      (require 'gptel))
+    (when (fboundp 'cj/ensure-gptel-backends)
+      (cj/ensure-gptel-backends))
+    (gptel-request prompt
+      :buffer buf
+      :position (with-current-buffer buf (point-max))
+      :stream t)
+    (display-buffer buf
+                    '((display-buffer-reuse-window
+                       display-buffer-pop-up-window)
+                      (window-height . 0.3)))
+    buf))
+
+(defun cj/gptel-quick-dismiss ()
+  "Kill the *GPTel-Quick* buffer if it exists."
+  (interactive)
+  (when-let ((buf (get-buffer cj/gptel-quick--buffer-name)))
+    (when-let ((win (get-buffer-window buf)))
+      (delete-window win))
+    (kill-buffer buf)))
+
+(defun cj/gptel-quick-continue ()
+  "Escalate the current quick-ask into a full *AI-Assistant* conversation.
+Reads the prompt and response from the *GPTel-Quick* buffer, seeds
+them into *AI-Assistant* under proper org headings, displays the
+side window, then dismisses the quick buffer."
+  (interactive)
+  (unless (eq major-mode 'cj/gptel-quick-mode)
+    (user-error "Not in a *GPTel-Quick* buffer"))
+  (let* ((prompt cj/gptel-quick--prompt)
+         (response (cj/gptel-quick--extract-response (buffer-string)))
+         (seed (cj/gptel-quick--seed-text prompt response)))
+    (unless prompt
+      (user-error "No prompt recorded in this buffer"))
+    ;; Ensure *AI-Assistant* exists in gptel-mode.
+    (unless (featurep 'gptel)
+      (require 'gptel))
+    (let ((ai-buf (get-buffer "*AI-Assistant*")))
+      (unless ai-buf
+        (when (fboundp 'cj/ensure-gptel-backends)
+          (cj/ensure-gptel-backends))
+        (gptel "*AI-Assistant*")
+        (setq ai-buf (get-buffer "*AI-Assistant*")))
+      (with-current-buffer ai-buf
+        (goto-char (point-max))
+        (insert seed))
+      (display-buffer-in-side-window
+       ai-buf '((side . right) (window-width . 0.4)))
+      (cj/gptel-quick-dismiss))))
+
+(provide 'ai-quick-ask)
+;;; ai-quick-ask.el ends here