roll: pigweed docs: Update changelog for July 2026 Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/452352 Original-Revision: 88af1ce547ff9fc197315187a76950fd809c19aa Rolled-Repo: https://pigweed.googlesource.com/pigweed/pigweed Rolled-Commits: 7c84c203cbe530..88af1ce547ff9f Roll-Count: 1 Roller-URL: https://cr-buildbucket.appspot.com/build/8673429702064166369 GitWatcher: ignore CQ-Do-Not-Cancel-Tryjobs: true Change-Id: If49e55dfadd4d7f87860a2d008eb3b809901525a Reviewed-on: https://pigweed-review.googlesource.com/c/zephyr/zephyr-bazel/+/455705