docs(vrl): add example syntax for valid expressions. (#21963)

* docs(vrl): add example syntax for valid expressions.

* fix spelling

* fix grammar and trailing whitespace from 'cargo vdev check fmt'

* run 'cue fmt' to pass 'make check-docs'

website/cue/reference/remap/syntax/expressions.cue

@@ -0,0 +1,22 @@
+package metadata
+
+remap: syntax: expressions: {
+	title: "Expressions"
+	description: """
+		VRL programs are made up of literal and dynamic expressions, described more in detail below.  Expressions can be separated by newline or semicolon in any combination.
+		"""
+
+	examples: [
+		"""
+			# newline delimited expressions
+			del(.user_info)
+			.timestamp = now()
+			.message = "hello world"
+			""",
+		"""
+			# semicolon delimited expressions
+			del(.user_info); .timestamp = now()
+			.message = "hello world"
+			""",
+	]
+}