fix(compose): default to quoting below, and focus the body on a reply

The previous commit fixed the cursor within each quote_position branch and
the user still saw the old layout, because the branches were already right:
what was wrong was the DEFAULT. quote_position shipped as `above`, and the
layout asked for is exactly what `below` already produced, a blank line at
the top with the quote underneath.

So the default flips, along with the fallback for a malformed value and the
warning naming it. Nothing needs an Upgrading note: compose has not been
released, so no config in the wild sets this.

Focus goes to the body whenever To: is already filled, which a Reply and a
Forward always are. The form's first widget took it otherwise, so the user
had to click into the editor before typing. A New message keeps the default,
since an empty To: is genuinely the first thing to fill in.

The focus test asserts on the window's focusWidget() rather than on
QWidget::hasFocus(): an unshown window is never active, so hasFocus() reads
false whatever the code does and would fail against a correct fix. Both
directions are mutation-checked, since focusing unconditionally passes the
reply case while breaking the new-message one.

1 files changed, 4 insertions, 1 deletions

diff --git a/src/config.h b/src/config.h
index 51fc1ee..3ddd76a 100644
--- a/src/config.h
+++ b/src/config.h
@@ -212,7 +212,10 @@ struct ComposeSettings
     /// reply_no_quote does not).
     enum class QuotePosition { Above, Below };
 
-    QuotePosition quotePosition = QuotePosition::Above;
+    /// Below by default: the reply is typed at the top and the quote sits
+    /// under it, which is what the user asked for and what every mail client
+    /// they compare against does. Above is bottom-posting and stays available.
+    QuotePosition quotePosition = QuotePosition::Below;
 
     /// Seeds the per-message toggle for New and Forward only. Reply and
     /// Reply-all seed from whether the original carried a text/html part,