chore(release): bump version to 0.7.0

OxiCloud v0.7.0 — "Slipstream". Version bump for the release; see the
GitHub release notes for the full changelog since v0.6.0.

https://claude.ai/code/session_01DCszkkU11LYxMEUWr4setK

Cargo.lock

@@ -4076,7 +4076,7 @@ dependencies = [
 
 [[package]]
 name = "oxicloud"
-version = "0.6.0"
+version = "0.7.0"
 dependencies = [
  "accept-language",
  "aes-gcm",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "oxicloud"
-version = "0.6.0"
+version = "0.7.0"
 edition = "2024"
 default-run = "oxicloud"