fix(ce-commit-push-pr): use body-file for PR descriptions (#757)

Author: tmchow

plugins/compound-engineering/skills/ce-commit-push-pr/SKILL.md

@@ -71,17 +71,22 @@ Use the current branch and existing PR check from context. If the current branch
 
 **Compare and confirm.** Briefly explain what the new description covers differently from the old one. Ask the user to confirm before applying. If the user provided focus, confirm it was addressed.
 
-If confirmed, apply with `gh pr edit`. Substitute `<TITLE>` verbatim; if it contains `"`, `` ` ``, `$`, or `\`, escape them or switch to single quotes. The body is best written to a temp file first to avoid shell-escaping the whole markdown body:
+If confirmed, apply with `gh pr edit`. Substitute `<TITLE>` verbatim; if it contains `"`, `` ` ``, `$`, or `\`, escape them or switch to single quotes.
+
+The body **must** be written to a temp file and passed via `--body-file <path>`. Never use `--body-file -`, stdin pipes, heredoc-to-stdin, or `--body "$(cat ...)"` — wrappers and stdin handling can silently produce an empty PR body while `gh` still exits 0 and returns a URL.
 
 ```bash
 BODY_FILE=$(mktemp "${TMPDIR:-/tmp}/ce-pr-body.XXXXXX") && cat > "$BODY_FILE" <<'__CE_PR_BODY_END__'
 <the composed body markdown goes here, verbatim>
 __CE_PR_BODY_END__
-gh pr edit --title "<TITLE>" --body "$(cat "$BODY_FILE")"
 ```
 
 The quoted sentinel keeps `$VAR`, backticks, and any literal `EOF` inside the body from being expanded.
 
+```bash
+gh pr edit --title "<TITLE>" --body-file "$BODY_FILE"
+```
+
 Report the PR URL.
 
 ---
@@ -178,7 +183,9 @@ When evidence is not possible (docs-only, markdown-only, changelog-only, release
 
 ### Step 7: Create or update the PR
 
-Apply via `gh pr create` (new PR) or `gh pr edit` (existing PR). The body is best written to a temp file first to avoid shell-escaping the whole markdown body. Substitute `<TITLE>` verbatim; if it contains `"`, `` ` ``, `$`, or `\`, escape them or switch to single quotes:
+Apply via `gh pr create` (new PR) or `gh pr edit` (existing PR). Substitute `<TITLE>` verbatim; if it contains `"`, `` ` ``, `$`, or `\`, escape them or switch to single quotes.
+
+The body **must** be written to a temp file and passed via `--body-file <path>`. Never use `--body-file -`, stdin pipes, heredoc-to-stdin, or `--body "$(cat ...)"` — wrappers and stdin handling can silently produce an empty PR body while `gh` still exits 0 and returns a URL.
 
 ```bash
 BODY_FILE=$(mktemp "${TMPDIR:-/tmp}/ce-pr-body.XXXXXX") && cat > "$BODY_FILE" <<'__CE_PR_BODY_END__'
@@ -191,7 +198,7 @@ The quoted sentinel keeps `$VAR`, backticks, and any literal `EOF` inside the bo
 #### New PR (no existing PR from Step 3)
 
 ```bash
-gh pr create --title "<TITLE>" --body "$(cat "$BODY_FILE")"
+gh pr create --title "<TITLE>" --body-file "$BODY_FILE"
 ```
 
 Keep the title under 72 characters; the writing reference already emits a conventional-commit title in that range.
@@ -207,7 +214,7 @@ The new commits are already on the PR from Step 5. Report the PR URL, then ask w
   3. If confirmed, apply with `gh pr edit`:
 
      ```bash
-     gh pr edit --title "<TITLE>" --body "$(cat "$BODY_FILE")"
+     gh pr edit --title "<TITLE>" --body-file "$BODY_FILE"
      ```
 
   Then report the PR URL (Step 8).