fix(ai): restore url-quote-magic for ? in zsh (#3304)

I discovered that since #3178, typing or pasting a `?` in a URL no
longer gets escaped by `url-quote-magic`. For example, pasting
`https://example.com/search?q=foo&test` would result in
`https://example.com/search?q=foo\&test` (leave the `?` unescaped, while
`&` still worked correctly).

The root cause is that Atuin binds `?` to `_atuin_ai_question_mark`,
which bypasses `url-quote-magic` in two ways:

1. **Typed `?`**: the else branch (non-empty buffer) appended `?`
directly to `LBUFFER` instead of delegating to `self-insert` which runs
`url-quote-magic`.

2. **Pasted `?`**: `bracketed-paste-magic` only [activates widgets whose
name matches
`self-*`](https://github.com/zsh-users/zsh/blob/99f578897614f318cdad76402a7d2423ce176b5a/Functions/Zle/bracketed-paste-magic#L24).
Since `_atuin_ai_question_mark` didn't match, pasted `?` characters fell
through to `zle .self-insert` — the raw built-in that inserts literally
without any URL escaping.

The fix renames the widget to `self-atuin-ai-question-mark` (Note: I am
not sure this is the best way but it is a relatively simple one). The
`self-` prefix satisfies `bracketed-paste-magic`'s `active-widgets`
pattern, so `?` in paste is processed by our widget and delegated to
`zle self-insert`, restoring `url-quote-magic` behaviour. The typed case
delegates to `zle self-insert` in the else branch for the same reason.

1 files changed, 9 insertions, 6 deletions

diff --git a/crates/atuin-ai/src/commands/init.rs b/crates/atuin-ai/src/commands/init.rs
index 6b23e936..77abc4f4 100644
--- a/crates/atuin-ai/src/commands/init.rs
+++ b/crates/atuin-ai/src/commands/init.rs
@@ -32,8 +32,10 @@ _atuin_ai_cleanup() {
     true
 }
 
-# Question mark at start of line - natural language mode
-_atuin_ai_question_mark() {
+# Question mark at start of line - natural language mode.
+# Named with 'self-' prefix so bracketed-paste-magic activates it during
+# paste, allowing url-quote-magic to escape ? in pasted URLs via self-insert.
+self-atuin-ai-question-mark() {
     # If buffer is empty or just contains '?', trigger natural language mode
     if [[ -z "$BUFFER" || "$BUFFER" == "?" ]]; then
         BUFFER=""
@@ -65,13 +67,13 @@ _atuin_ai_question_mark() {
             zle reset-prompt
         fi
     else
-        LBUFFER="${LBUFFER}?"
+        zle self-insert
     fi
 }
 
 # Set up keybindings
-zle -N _atuin_ai_question_mark
-bindkey '?' _atuin_ai_question_mark # Question mark
+zle -N self-atuin-ai-question-mark
+bindkey '?' self-atuin-ai-question-mark # Question mark
 "#
     .trim()
 }
@@ -193,13 +195,14 @@ mod tests {
     #[test]
     fn test_generate_zsh_integration() {
         let result = generate_zsh_integration();
-        assert!(result.contains("_atuin_ai_question_mark"));
+        assert!(result.contains("self-atuin-ai-question-mark"));
         assert!(result.contains("bindkey"));
         assert!(result.contains("atuin ai inline --hook"));
         assert!(result.contains("__atuin_ai_print__"));
         assert!(result.contains("__atuin_ai_cancel__"));
         assert!(result.contains("__atuin_ai_execute__"));
         assert!(result.contains("__atuin_ai_insert__"));
+        assert!(result.contains("zle self-insert"));
     }
 
     #[test]