The Unix-VFS MAX_PATHNAME bump from 512 to 4096 shipped with the daemon
work but left no paper trail, so the next amalgamation refresh would
silently revert it. Document it in vendored/sqlite3/PATCHES.md with the
rationale and re-apply procedure, and point to it from THIRD_PARTY.md.
Signed-off-by: Martin Vogel <martin.vogel.tech@gmail.com>
