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/collapse_layout.py b/test/collapse_layout.py
index e549bd37..244ee57a 100644
--- a/test/collapse_layout.py
+++ b/test/collapse_layout.py
@@ -29,7 +29,7 @@ def geometry(client, names):
 
 def toggle(client, serial):
     """Execute the default tag's Collapse word without changing any body or tag."""
-    pane = f'/self/pane/{serial}'
+    pane = f'/pane/{serial}'
     tag = client.read(pane + '/tag')
     at = tag.rfind(b' Collapse')
     require(at >= 0, 'default pane tag lacks Collapse')
@@ -57,8 +57,8 @@ def run(args):
             for index, label in enumerate(names):
                 if index:
                     serials.append(new_pane(client, b''))
-                pane = f'/self/pane/{serials[index]}'
-                client.write(pane + '/ctl', ('name ' + label + '\n').encode())
+                pane = f'/pane/{serials[index]}'
+                client.write(pane + '/name', (label + '\n').encode())
                 client.write(pane + '/body', contents, truncate=True)
             original = require(wait_for(lambda: geometry(client, names)), 'four pane tags not visible')
             require(all(height > 1 for _, height in original), f'fixture has no body room: {original}')
@@ -82,7 +82,7 @@ def run(args):
                 require(wait_for(lambda: geometry(client, names) == original),
                         f'expansion did not restore original geometry: {geometry(client, names)}')
             for serial in serials:
-                require(client.read(f'/self/pane/{serial}/body') == contents, 'Collapse changed pane contents')
+                require(client.read(f'/pane/{serial}/body') == contents, 'Collapse changed pane contents')
             require((root / (name + '.txt')).read_bytes() == b'initial\n', 'fixture source file changed')
     print(f'{"TTY" if args.tty else "SDL"}: 7 local collapse/expand pairs, exact unrelated pane geometry, and content preservation passed')