Refactor panes and filesystem; replace FUSE with 9P

Consolidate pane, layout, memory and host code. Serve 9P by default over Unix sockets, with runtime mounts and optional TCP/QUIC transports. Remove FUSE and obsolete proof-of-concept examples.

Fix highlighting and terminal-history performance, expand differential and stress-test infrastructure, sort navigation results while preserving the next occurrence, add syntax-colored Braille minimaps, remove SPC-k, and document 9P interaction as a repository skill.

1 files changed, 21 insertions, 26 deletions

diff --git a/src/tutor.txt b/src/tutor.txt
index f712ab85..b2110dd8 100644
--- a/src/tutor.txt
+++ b/src/tutor.txt
@@ -230,11 +230,9 @@
  WHAT A DAEMON CAN ALSO DO
  A detached session serves acme's control filesystem like any other:
 
-   pardes --detach=work --fs      the tree under $XDG_RUNTIME_DIR
-   pardes --detach=work --fs9     the same tree, as 9P on a unix socket
+   pardes --detach=work          9P on the session's default unix socket
 
- Either, both or neither. That is what makes a daemon scriptable while
- nobody is looking at it — see part 6.
+ Every native session is scriptable over 9P — see part 6.
 
  The socket lives in $XDG_RUNTIME_DIR (else ~/.local/state/pardes),
  created 0700, never /tmp: it carries keystrokes into a live editor.
@@ -368,7 +366,7 @@ typed
  abandons it, and so does any key that leads nowhere.
 
    SPC ?        list every path
-   SPC k        Kill        SPC d      Del
+   SPC d        Del         Kill remains available in the topbar.
    SPC f s      Save        SPC f f    Find      SPC f n  New
    SPC y Y p P R    the system clipboard
    SPC w h/j/k/l    focus a neighbouring pane
@@ -397,46 +395,43 @@ typed
  plugin API, no interpreter and no rebuild. A program that opens files
  IS an extension.
 
-   pardes --fs      acme's control files over FUSE
-   pardes --fs9     the same tree as 9P on a unix socket
+   pardes          the 9P socket opens by default
 
  A directory per pane holding `body`, `tag`, `ctl`, `addr`, `data`,
  `event`, `pty/` and the rest, plus `index`, `cons` and `new/` at the
- top. Every pane shell is told `$PARDES_FS` and `$PARDES_PANE`, so a
- script in a pane addresses its own window with no arguments:
+ top under /self. Every pane shell receives `$PARDES_9P` (the socket)
+ and `$PARDES_PANE` (its serial). Use a 9P client to read and write:
 
-     echo hello >> $PARDES_FS/$PARDES_PANE/body
-     cat $PARDES_FS/index
-     echo hi > $PARDES_FS/new/body
+     /self/pane/<serial>/body
+     /self/index
+     /self/new/ctl
 
  A terminal pane also has `pty/`:
 
-     echo 'winsize 100 30' >> $PARDES_FS/3/pty/ctl
-     echo 'sig INT'        >> $PARDES_FS/3/pty/ctl
-     echo 'make -j8'       >> $PARDES_FS/3/pty/data
+     /self/pane/3/pty/ctl     winsize, sig
+     /self/pane/3/pty/data    terminal input/output
 
  Over 9P the same tree answers plan9port, from anywhere:
 
      9p -a $XDG_RUNTIME_DIR/pardes-9p-work.sock ls /
-     9p -a $XDG_RUNTIME_DIR/pardes-9p-work.sock read /index
+     9p -a $XDG_RUNTIME_DIR/pardes-9p-work.sock read /self/index
 
  ...and pardes is a 9P CLIENT too, so one session can read another's:
 
-     9p work.sock /1/body        the `9p` word: opens it in a pane
+     pardes --mount=peer=work
+     /n/peer/self/pane/1/body    Look opens the other session's body
 
  TWO THINGS WORTH KNOWING. While a program holds a pane's `event` file
  open, MIDDLE AND RIGHT CLICKS IN THAT PANE BELONG TO IT: pardes reports
  them and performs nothing, so that pane's tag can carry the program's
- own words (examples/acmefs/life.py puts Step/Run/Clear there). The
- keyboard is never suppressed, and the clicks come back when it exits.
+ own words. The keyboard is never suppressed, and the clicks come back
+ when it exits.
 
  And writing an event record back — `origin type q0 q1` — makes pardes
  perform the Look or Exec it names. That is arbitrary command execution
- by design, the same door acme has always had, which is why the mount
- sits under $XDG_RUNTIME_DIR at 0700 and why both flags are opt-in.
+ by design. The socket sits in the user's private runtime directory.
 
- examples/README.md is the client's guide; docs/acme-fs.md compares this
- implementation with acme's file by file; docs/9p.typ is the 9P note.
+ docs/fs.md describes the filesystem and mount paths.
 
 
 =================================================================
@@ -466,7 +461,7 @@ typed
             Attach / Detach            the same, as words (SPC s a / s D)
             the pane shells belong to the SESSION and never stop
             N frontends share ONE screen at the smallest common grid
-            --fs and --fs9 work in a daemon too
+            the default 9P socket works in a daemon too
 
  KEYS       h j k l  w b e  0 $ ^  gg ge  f F t T  v x  d c y p
             i a I A o O   u undo  U redo
@@ -480,8 +475,8 @@ typed
             / is a case-insensitive SUBSTRING search, not a regex
             SPC is the leader (SPC ? lists every path)
 
- SCRIPTING  --fs  acme's files over FUSE;  --fs9  the same over 9P
-            $PARDES_FS/<id>/{body,tag,ctl,addr,data,event,pty/}
+ SCRIPTING  9P is served by default on $PARDES_9P
+            /self/pane/<id>/{body,tag,ctl,addr,data,event,pty/}
             a script holding `event` owns that pane's middle and right
                 clicks; writing a record back runs it