Crt, Ripple and Glitch take a level, 0 to 3, tunable at run time

Coordinator's request: `Crt 0..3` (likewise Ripple, Glitch), 0 off, `on`
the default level 2 (the polished rewrite), `off` and a bare word as
before. The level is one uniform (pardesLevel, beside pardesOpaque in the
prefix's own block); each pass picks its constants by it. Level 3 is at
least as strong as the old effects, measured as pixels changed by more
than 8 in a channel against a plain frame: Crt 18.3% (old 17.4%), Ripple
11.1% (9.5%), Glitch 9.3% a frame (8.1%); Glitch's level raises how often
it bursts as well as how hard. Config and ctl report `Crt 2` / `Crt off`.

Shared files touched: ninep/ctl.zig (the report line). Not touched:
pardes.zig, Messages.zig, mouse.zig, gui.zig, detached/*.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/ninep/ctl.zig b/src/ninep/ctl.zig
index ed10dd70..cd327d03 100644
--- a/src/ninep/ctl.zig
+++ b/src/ninep/ctl.zig
@@ -263,7 +263,7 @@ fn writeSettings(p: *Pardes, w: *std.Io.Writer) !void {
             // Bare, it names the default directory.
             .dump_dir => if (s.dump_dir.len > 0) try w.print("{s} {s}\n", .{ word, s.dump_dir.get() }) else try w.print("{s}\n", .{word}),
             .transition => |effect| try w.print("{s} {s}\n", .{ word, if (s.panel_transition == effect) "on" else "off" }),
-            .scene => |effect| try w.print("{s} {s}\n", .{ word, if (s.post.has(effect)) "on" else "off" }),
+            .scene => |effect| if (s.post.level(effect) == 0) try w.print("{s} off\n", .{word}) else try w.print("{s} {d}\n", .{ word, s.post.level(effect) }),
             .shader => for (s.post.list()) |entry| if (entry.scene == null) try w.print("{s} {s}\n", .{ word, entry.path.get() }),
             .shader_animation => try w.print("{s} {s}\n", .{ word, @tagName(s.shader_animation) }),
         }