Bump version to 1.4.0

Naming change to ldh-Generate* is breaking for any external workflow
JSON referencing the bare names, so a minor bump is more appropriate
than 1.3.1.

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

Author: namedgraph

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "web-algebra"
-version = "1.3.1"
+version = "1.4.0"
 description = "Composable RDF operations in JSON"
 readme = "README.md"
 license = "Apache-2.0"