Keep an edit under a name, not just on the clipboard

FR-DEV-6 asks for three things — named presets, copy/paste between
images, and batch-apply to a selection. The last two have been here for
a while; this is the first.

The format is the sidecar's, deliberately. A preset *is* the non-default
half of a version, so the lines are the same lines keyed the same way,
which makes the two files diffable against each other and lets someone
debugging an edit paste a block from one into the other. One file rather
than one per preset: a preset per file makes the name a path, and every
name then has to survive a filesystem — a `/` becomes a directory, a
name differing only in case collides on one platform and not another,
and renaming becomes two operations that can half-fail. As a key in a
document it is none of those.

Unknown *parameters* needed no machinery. `Preset` already holds
whatever keys it is given and resolves them against the descriptors only
at apply time, so one written by a newer build survives by being stored.
Only lines that are not `op.param = float` at all are preserved
verbatim, which is the sidecar's version-skew promise made here too.

Applying is the paste path with a different source, so a preset reaches
a selection through the sidecar read-modify-write that was already
there: no graph, no decode, no GPU, forty files or one.

Two smaller decisions worth the record. A library that fails to parse is
held empty in memory and *not* written back over — settings regenerate
themselves and this is work, so a parse failure must not be the moment
it is destroyed. And every save persists immediately and rolls the
in-memory copy back if the write fails, so the sheet never lists a
preset the file does not have.

The grid's "Presets" button is gated on the selection alone, unlike the
"Paste to 40" beside it. That button needs a clipboard armed this
session; the preset list is whatever was saved last month, and hiding it
behind an unrelated action is what makes a feature only its author knows
about.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

ui/dr-ui/src/lib.rs

@@ -39,6 +39,7 @@ mod library_ui;
 mod live_style;
 mod masks_ui;
 mod net_runtime;
+mod preset_store;
 mod presets;
 mod remote;
 mod segmentation;
@@ -2021,6 +2022,24 @@ pub fn run(paths: Vec<PathBuf>) -> Result<()> {
             collections.clone(),
         );
 
+        // TRACES: FR-DEV-6
+        // The saved half of the same requirement, wired from the same bundle:
+        // applying a named preset to the open image is the paste path with a
+        // different source.
+        presets::wire_named(
+            &window,
+            presets::NamedPresets::open(),
+            presets::Develop {
+                session: session.clone(),
+                rows: rows.clone(),
+                redraw: redraw.clone(),
+                open: open_image.clone(),
+            },
+            settings.clone(),
+            library.clone(),
+            collections.clone(),
+        );
+
         // Close the knot left open beside `open_from_library`: the grid's
         // "‹ Library" button was wired before there was a session to save.
         let weak = window.as_weak();