viewer: fix e editor handoff never returning to the viewer

Running the editor via `$SHELL -ic` let the interactive shell enable job
control and take over the TTY's foreground process group; when it exited it
left the TTY pointing at a dead group, so the relaunched Ink viewer died with
`setRawMode failed with errno: 5` instead of coming back. Run the editor via a
plain non-interactive `-c` shell, which never touches the foreground group.
Env vars like $EDITOR still resolve in the template; rc-file aliases no
longer do (docs updated).

Also replace a stray NUL byte in src/pr.mjs (inside latestChecks' dedup key,
clearly meant to be a space) that made git/grep treat the file as binary.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: owenconti

index.jsx

@@ -171,9 +171,13 @@ while (true) {
   // released the terminal, so stdio "inherit" hands the real TTY to a terminal
   // editor (vi/nano) and blocks until it exits; then we re-read the working tree
   // (they may have edited the file) and re-launch the viewer on the fresh diff.
+  // The shell must NOT be interactive (`-i`): an interactive shell enables job
+  // control, moves the TTY's foreground process group to itself, and leaves it
+  // pointing at a dead group on exit — the relaunched viewer then dies with
+  // `setRawMode failed with errno: 5` instead of coming back.
   if (handoff.edit) {
     const shell = process.env.SHELL || "/bin/sh";
-    const res = spawnSync(shell, ["-ic", handoff.edit.cmd], { stdio: "inherit" });
+    const res = spawnSync(shell, ["-c", handoff.edit.cmd], { stdio: "inherit" });
     if (res.error) console.error(`\norbit-diff: couldn't launch editor: ${res.error.message}`);
     let next;
     try {

orbit-diff.config.example.js

@@ -18,10 +18,10 @@ export default {
   model: "claude-opus-4-8", // any model id Pi knows for the provider above
   thinkingLevel: "medium", // off | minimal | low | medium | high | xhigh
   // Pressing `e` on a file in the diff viewer opens it in this editor. The {file}
-  // token becomes the file's absolute path (shell-quoted) and the command runs in
-  // your login shell (aliases/functions work). Terminal editors are fine — the
-  // viewer hands over the terminal while the editor runs and reloads the diff when
-  // you exit it. Empty disables `e`.
+  // token becomes the file's absolute path (shell-quoted) and the command runs via
+  // your shell non-interactively (env vars like $EDITOR resolve; rc-file aliases
+  // don't). Terminal editors are fine — the viewer hands over the terminal while
+  // the editor runs and reloads the diff when you exit it. Empty disables `e`.
   editor: "", // e.g. "vi {file}"  ·  "code {file}"  ·  "$EDITOR {file}"
   review: {
     concurrency: 4, // how many files to review in parallel (1–8)

src/ai/config.mjs

@@ -28,9 +28,10 @@ export const DEFAULTS = {
   thinkingLevel: "medium",
   // Command run when you press `e` on a file in the diff viewer to open it in your
   // editor. The `{file}` token is substituted with the file's absolute path
-  // (shell-quoted); the command runs in your login shell so aliases/functions
-  // resolve. Terminal editors work — the viewer hands over the terminal while it
-  // runs and reloads the diff when you exit. Empty = `e` is disabled.
+  // (shell-quoted); the command runs via your shell non-interactively (env vars
+  // like $EDITOR resolve; rc-file aliases don't). Terminal editors work — the
+  // viewer hands over the terminal while it runs and reloads the diff when you
+  // exit. Empty = `e` is disabled.
   //   e.g. "vi {file}"  ·  "code {file}"  ·  "$EDITOR {file}"
   editor: "",
   review: { concurrency: 4 },
@@ -79,8 +80,9 @@ export default {
   model: "claude-opus-4-8", // any model id Pi knows for the provider above
   thinkingLevel: "medium", // off | minimal | low | medium | high | xhigh
   // Pressing \`e\` on a file opens it in this editor. {file} = the file's absolute
-  // path (shell-quoted); runs in your login shell. Terminal editors work — the
-  // viewer hands over the terminal and reloads the diff when you exit. Empty = off.
+  // path (shell-quoted); runs via your shell ($EDITOR etc. resolve). Terminal
+  // editors work — the viewer hands over the terminal and reloads the diff when
+  // you exit. Empty = off.
   editor: "", // e.g. "vi {file}"  ·  "code {file}"  ·  "$EDITOR {file}"
   review: {
     concurrency: 4, // how many files to review in parallel (1–8)