install.sh: respect /ext disabled state on re-run

When linking, check for <name>.ts.off pointing into this repo and skip
relinking if found. Means a previously /ext-disabled extension stays
disabled across install.sh re-runs (e.g. when adding a new extension).

README + AGENTS updated with the new behavior.

AGENTS.md

@@ -176,6 +176,11 @@ effect without restarting pi.
 - **Symlink-friendly.** `fs.renameSync` renames the symlink itself; the repo
   target is untouched. Toggling an extension installed by this repo is
   reversible without re-running `install.sh`.
+- **`install.sh` respects the disabled state.** When linking, the installer
+  first checks for a `<name>.ts.off` symlink pointing into this repo and
+  skips re-linking if found. So re-running `./install.sh` (e.g. to pick up
+  a newly added extension) does not silently re-enable a previously
+  `/ext`-disabled extension.
 - **Subdir extensions are read-only in v1.** `name/index.ts` shapes show up in
   the listing with a `[dir]` tag but cannot be toggled — the cleanest disable
   for a directory would need a hidden-prefix or move-aside dance that adds

README.md

@@ -176,6 +176,7 @@ Registers `/ext` — a slash command that lists extensions in `~/.pi/agent/exten
 **Notes:**
 - Subdirectory-style extensions (`name/index.ts`) are listed read-only — v1 doesn't toggle them. Move the directory aside manually if needed.
 - `install.sh --uninstall` cleans up both `.ts` and `.ts.off` symlinks pointing into this repo, so a disabled extension won't be left behind.
+- Re-running `./install.sh` respects a prior `/ext` disable: if `<name>.ts.off` already exists, the installer leaves it alone instead of silently re-enabling.
 
 ## Adding a new extension
 

install.sh

@@ -151,9 +151,17 @@ do_install() {
         in_install_set "$bare" || continue
 
         local dest="${EXTENSIONS_DEST}/${name}"
+        local disabled="${dest}.off"
 
         note "Linking ${name}"
 
+        # Respect a prior /ext disable: if <name>.ts.off exists and points
+        # into this repo, leave it alone. ext-toggle will flip it back.
+        if [[ -L "$disabled" ]] && link_into_repo "$disabled"; then
+            ok "${name} kept disabled (${name}.off present)"
+            continue
+        fi
+
         if [[ -e "$dest" || -L "$dest" ]]; then
             if link_into_repo "$dest"; then
                 ok "${name} already linked"