fix: safe_send routes embed= + fails loud on unknown kwargs; embed helpers deep-copy (no input mutation)

Signed-off-by: disqualifier <dev@disqualifier.me>

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "dpy_commons"
-version = "0.1.2"
+version = "0.1.3"
 description = "Shared discord.py utilities — message/embed parsing, limit-fitting, link extraction, chunking, timestamps, await-prompts, limit-safe send. Config-free, installable."
 requires-python = ">=3.10"
 dependencies = [