output panes remember the command that opened them

An output buffer was a file pane with a flag, and everything special about it
was re-derived from outside by asking the wrong question: the buffer NAME
("+Search", "+Help"), a parallel search_kind field, and f.output predicates
sprinkled through kind-agnostic code.

Now it carries its Origin — the Builtin, or the lsp.Kind for the five gotos
helix binds as motions rather than words — plus that command's argument, and
one Traits table answers every question the scattered code used to ask: what
it is called, whether n/N steps it, whether it is a doc for layout, whether
Esc dismisses it, whether it saves. The name is derived FROM the command
instead of being the thing that identifies it.

Adding a kind of output pane is adding a row. No golden moved.

1 files changed, 7 insertions, 2 deletions

diff --git a/src/dump.zig b/src/dump.zig
index 51221197..0f8cb810 100644
--- a/src/dump.zig
+++ b/src/dump.zig
@@ -68,8 +68,13 @@ pub const File = struct {
     path: []const u8 = "",
     content: []const u8 = "",
     content_b64: []const u8 = "",
-    /// an output buffer (no file behind the name) — see pardes.File.output
-    output: bool = false,
+    /// non-empty = an output buffer (no file behind the name): the WORD of the
+    /// command that opened it, plus that command's argument — see
+    /// output_pane.Origin. A word rather than an integer for the reason every
+    /// other command in here is a word: reordering builtins.zig stays free,
+    /// and a dump stays something a person can read.
+    origin: []const u8 = "",
+    origin_arg: []const u8 = "",
 };
 
 pub const Image = struct {