Flatten the 9P control tree and move it out of fs.zig

The served tree loses the self/ level: /index /ctl /new /log /screen
/listeners /pane/<n>/... /os, with /src only in -Dembed-sources=true builds
(default off, on for esp32p4). ctl speaks the editor's own language with two
lowercase verbs, look TEXT and exec TEXT, plus acme's addr verbs; the new/
factory directory becomes one clone file; cons is gone (exec Msg); name and
sel are files; stats report real lengths, modes and mtimes; /log streams
pane new/del/rename/save events. The tree code lives in src/ninep/
(tree, pane, ctl, addr, pty, events, screen, sources); fs.zig keeps host
access, mounts, resolution and find/grep. Same engine and transports.
README (fs-help.txt) and docs rewritten; tests updated and extended.

Co-Authored-By: Claude Fable 5.1 <[email protected]>

1 files changed, 4 insertions, 4 deletions

diff --git a/test/panes.zig b/test/panes.zig
index 81015356..d3c29856 100644
--- a/test/panes.zig
+++ b/test/panes.zig
@@ -834,10 +834,10 @@ const ClickCursorTests = struct {
         for (0..2) |_| p.update(.{ .mouse = .{ .button = .wheel_down, .kind = .press, .col = x + 2, .row = y + 4 } });
         try std.testing.expectEqual(@as(usize, 2), pane.file.?.scroll);
         _ = try p.render(frame.allocator());
-        const event_node = filesystem.Node.of(pane.serial, .event);
-        const opened = filesystem.handle(p, .{ .tag = 0, .op = .open, .node = event_node });
+        const event_node = pardes.ctlfs.Node.of(pane.serial, .event);
+        const opened = pardes.ctlfs.handle(p, .{ .tag = 0, .op = .open, .node = event_node });
         try std.testing.expectEqual(.ok, opened.status);
-        defer _ = filesystem.handle(p, .{ .tag = 0, .op = .release, .node = event_node, .handle = opened.handle });
+        defer _ = pardes.ctlfs.handle(p, .{ .tag = 0, .op = .release, .node = event_node, .handle = opened.handle });
 
         for ([_]pardes.Mouse.Button{ .middle, .right }) |button| {
             const events = &p.fs.panes[0].events;
@@ -1907,7 +1907,7 @@ test "file history allocation precedes a filesystem read with side effects" {
     const original = p.panes[0].?;
     const serial = p.next_serial;
     failing.fail_index = failing.alloc_index + 2;
-    try std.testing.expectError(error.OutOfMemory, panes.File.open(p, 1, "/n/self/new/ctl", 0));
+    try std.testing.expectError(error.OutOfMemory, panes.File.open(p, 1, "/n/self/new", 0));
     try std.testing.expect(failing.has_induced_failure);
     try std.testing.expectEqual(original, p.panes[0].?);
     try std.testing.expectEqual(serial, p.next_serial);