Open presets from a menu at the foot of the tool rail

Presets were a "Presets…" button in develop's top bar that opened a
sheet over the photograph, so applying one was two clicks with the
picture covered. They are now an entry pinned to the bottom of the tool
rail, apart from the tools because a preset arms nothing, and it opens a
menu beside the rail: the same sectioned rows the sheet lists, one click
to apply to the open photograph. The menu's last row, "Save or manage…",
opens the sheet, which keeps saving, renaming, reverting and importing,
since those take a name or a path.

The menu is a PopupWindow for the film list's reasons, with the list in
a clipped box of its own; the Flickable alone let its last row draw over
the manage row. Choosing from it zeroes preset-apply-count before
applying, since the grid may have left its selection count there.

The manual says where presets are now and gains a picture of the open
menu. The scenes reach the sheet through the menu and aim the manage
row from the rail's entry, as the film list's rows are aimed, because
the automation reports a popup's elements in the popup's coordinates.

docs/manual/index.html

@@ -342,10 +342,13 @@ a gradient over the sky whose <code>Print Exposure</code> burns it in.</p>
 <figure><img loading="lazy" src="media/film-local.gif" alt="Kodak Ektar 100 on the whole frame, a gradient turned to cover the sky, its Print Exposure raised to burn the sky in, then holding Before"><figcaption>Kodak Ektar 100 on the whole frame, a gradient turned to cover the sky, its Print Exposure raised to burn the sky in, then holding Before</figcaption></figure>
 <h3 id="history-snapshots-presets">History, snapshots, presets</h3>
 <p>Every change is a step; <code>Undo</code> and the History panel walk them. <code>Snapshot</code>
-keeps the current state under a name. <code>Presets…</code> saves the settings to
-apply elsewhere, and imports Lightroom presets — <code>Folder…</code> for a folder of
-them, <code>.xmp file…</code> for one.</p>
-<p>The sheet lists your own presets first, then the ones DarkRoom ships —
+keeps the current state under a name. <code>Presets</code>, at the foot of the tool
+rail on the left, opens a menu of presets beside the photograph; choosing
+one applies it. The menu's last row, <code>Save or manage…</code>, opens the presets
+sheet, which saves the settings to apply elsewhere, renames and deletes
+them, and imports Lightroom presets — <code>Folder…</code> for a folder of them,
+<code>.xmp file…</code> for one.</p>
+<p>The menu and the sheet list your own presets first, then the ones DarkRoom ships —
 Essentials, Skies, and colour, cinema and black-and-white film, one measured stock
 each. A shipped preset is a look: it changes what it names and leaves the
 photograph's own corrections alone, as an imported Lightroom preset does.
@@ -353,6 +356,7 @@ Saving under a shipped preset's name makes your version the one that name
 applies, marked <em>changed</em>; <code>Revert</code> brings the shipped one back, and renaming
 yours makes it one of your own. A film preset carries its stock: choosing one
 sets the <code>Film</code> chooser and leaves the rest of the edit where it was.</p>
+<figure><img loading="lazy" src="media/presets-menu.png" alt="The presets menu open beside the tool rail, over the photograph"><figcaption>The presets menu open beside the tool rail, over the photograph</figcaption></figure>
 <figure><img loading="lazy" src="media/presets.png" alt="The presets sheet: a name for the current edit, the shipped Essentials, importing, and what an apply carries"><figcaption>The presets sheet: a name for the current edit, the shipped Essentials, importing, and what an apply carries</figcaption></figure>
 <figure><img loading="lazy" src="media/presets-film.gif" alt="Scrolling down the shipped presets to the black-and-white films, applying Ilford HP5 Plus, then holding Before"><figcaption>Scrolling down the shipped presets to the black-and-white films, applying Ilford HP5 Plus, then holding Before</figcaption></figure>
 <h3 id="copying-settings">Copying settings</h3>
@@ -360,7 +364,7 @@ sets the <code>Film</code> chooser and leaves the rest of the edit where it was.
 or Ctrl+V, puts them on another, and says what it would paste — how many
 adjustments, and whether the crop comes too. In the grid, <code>Paste to N</code> on the
 selection bar pastes onto every photograph selected. Which kinds of edit a
-copy carries is chosen in <code>Presets…</code>, or with Ctrl+Shift+C: a look carried
+copy carries is chosen in the presets sheet, or with Ctrl+Shift+C: a look carried
 across a shoot usually leaves each frame's own crop alone.</p>
 <h2 id="merging-a-panorama">Merging a panorama</h2>
 <p>Select the frames, then <code>Merge to panorama</code> from the selection bar. The