chore(deps): add regex, hex, percent-encoding for v1.1.0 stdlib

Workspace deps for the seven Rhai utility modules that follow in this
PR. `rand`, `base64`, `uuid`, `chrono`, `serde_json` are already in
the workspace and reused as-is — only the genuinely new ones land here.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

crates/executor-core/Cargo.toml

@@ -18,3 +18,10 @@ tracing.workspace = true
 uuid.workspace = true
 chrono.workspace = true
 rhai.workspace = true
+
+# Stdlib utility modules — see crates/executor-core/src/sdk/stdlib/.
+regex.workspace = true
+rand.workspace = true
+base64.workspace = true
+hex.workspace = true
+percent-encoding.workspace = true