feat(compose): lay the composer out by scope

Items 142, 143, 144 and 145, to the layout the user described.

The composer had one addToolBar carrying three scopes at once: text
formatting, message composition, and the terminal action. It read as a menu
bar that is not one. There is now no window toolbar at all.

  From:    [.............]        +--------+
  To:      [.........] [v Cc/Bcc] |   Send |
  Subject: [...........................]   +
  [B][I][</>][S][link]["]   [Attach] [Send as HTML]
  +---------------------------------------------+
  | message text                                |
  +---------------------------------------------+
  [Remove]  * report.pdf        <- only when attached

Send is a large icon-above-text button beside the headers: it is the
terminal action and carries the weight to match. Formatting is a toolbar
widget in the central column directly above the text it formats, icon-only
with the words kept as tooltips, which is where a tooltip stops being
decoration. Attach and the HTML toggle ride the right end of that bar, past
a stretch, because neither formats text. Remove attachment sits with the
list it acts on and appears only once something is attached.

"Also send a formatted copy" becomes "Send as HTML": the old label described
a mechanism without naming it, leaving the reader to infer that "formatted"
meant HTML and that "copy" meant a MIME part rather than a second message.

Cc and Bcc hide behind a disclosure beside To:. revealCcBccIfUsed() only
ever shows, never hides, so nothing but the user's own click can make a
field holding an address invisible: a hidden recipient is a message going
somewhere the sender cannot see, which is worse than the clutter this
removes. The label is hidden with each field, since a QFormLayout holds the
two as separate items and hiding the line edit alone strands a "Cc:" over
empty space.

Two send-lock faults, one predicted and one not. The backlog warned that
setInputsEnabled() disabled the single toolbar wholesale, so the send-path
test was strengthened to name every control BEFORE the split; it then caught
Attach live during a countdown, where a file appended after MessageBuilder
has run is either dropped or added to bytes already sent, silently either
way. With every control named it failed again on format_bold: disabling a
QToolBar greys its buttons but leaves each QAction enabled, so Ctrl+B during
a send would have edited a message already being built, through a button
that looked unavailable. setInputsEnabled() now walks the bar's actions too.

The Italian translation is refreshed; lrelease reports 477 finished, 0
unfinished.

1 files changed, 11 insertions, 0 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index da2156c..c0a567c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -23,6 +23,14 @@ point at which they are stable.
   reply follows what the message being answered used.
 - Drafts autosave to the account's `drafts` folder as ordinary Maildir files,
   so mbsync carries them to the server and another client can pick one up.
+- **The composer is laid out by scope.** Send is a large button beside the
+  headers rather than one more entry in a row of formatting buttons; the
+  formatting controls are icons on their own bar directly above the editor,
+  with Attach and Send as HTML at its right end; Remove attachment appears
+  beside the attachment list, and only once something is attached.
+- Cc and Bcc hide behind a disclosure next to To:, and reveal themselves
+  whenever either already carries a value, so a reply or a draft never hides
+  a recipient.
 - **A button bar over the message pane.** Reply and Forward sit directly
   above the message, with Toggle HTML at the right end. Forward had been
   reachable only from the Message menu.
@@ -48,6 +56,9 @@ point at which they are stable.
 
 ### Changed
 
+- "Also send a formatted copy" is now "Send as HTML", which says what it
+  does. It moved from a checkbox above the editor to the right end of the
+  formatting bar.
 - The main toolbar keeps the actions that need no particular message
   (Compose, Sync, Archive, Delete, Mark all read, Undo). Reply moves to the
   new message-pane bar, where Forward joins it.