export-pdf.sh silently discards the PDF when the output path is relative

Summary

scripts/export-pdf.sh never makes the output path absolute, then cds into its temp directory. When the second argument is a relative path, node writes the PDF inside the temp directory, which is removed on exit. The script prints ✓ PDF exported successfully! and leaves no file.

The script's own usage example is the failing case:

#   bash scripts/export-pdf.sh ./presentation.html ./presentation.pdf

Mechanism

L85-88   # Resolve output to absolute path
         OUTPUT_DIR=$(dirname "$OUTPUT_PDF")     # dirname "./x.pdf" -> "." , still relative
         mkdir -p "$OUTPUT_DIR"
         OUTPUT_PDF="$OUTPUT_DIR/$(basename "$OUTPUT_PDF")"

L352     cd "$TEMP_DIR"                          # CWD moves
L389     node "$TEMP_SCRIPT" ... "$OUTPUT_PDF" ...   # writes relative to TEMP_DIR
L397     rm -rf "$TEMP_DIR"                      # takes the PDF with it

L76 does resolve INPUT_HTML correctly with cd ... && pwd; the output block is missing that step. Note this also means the no-second-argument path works fine, because L82 derives the output from the already-absolute INPUT_HTML. So the bug only shows when someone passes an explicit relative output path, which is exactly what the documented examples do.

The only surface symptom is the du: cannot access '<path>': No such file or directory line from the file-size step after the success banner.

Reproduction

bash scripts/export-pdf.sh /abs/path/deck.html ./out.pdf
# -> "✓ PDF exported successfully!"  and no ./out.pdf anywhere on disk

Observed on a 40-slide deck: all 40 slides captured, "Assembling PDF...", success banner, no file. The same deck with an absolute second argument produced a correct 3.5 MB PDF.

Fix

One line, after the mkdir -p:

OUTPUT_DIR=$(dirname "$OUTPUT_PDF")
mkdir -p "$OUTPUT_DIR"
OUTPUT_DIR=$(cd "$OUTPUT_DIR" && pwd)          # <- add this
OUTPUT_PDF="$OUTPUT_DIR/$(basename "$OUTPUT_PDF")"

Verified after the change: the same relative-path invocation writes a valid PDF at the requested path.

Environment

Linux (WSL2), bash 5.2, node v22. The logic is platform independent, so macOS should behave the same, but I only tested on Linux. Checked against main as of today; scripts/export-pdf.sh L85-88 unchanged.

Happy to open a PR if useful.