release: kirby-cost 0.4.0

Campaign rule overrides, the engine/damage + engine/rolls modules kirby-combat
and kirby-sheet now import, and the STR END-cost fix.

Published 0.3.0 predates all of it by 36 commits, which made both downstream
packages' `kirby-cost>=0.3.0` floor a lie: kirby_cost.engine.damage,
kirby_cost.engine.rolls, TemplateData.defense, AdderTemplate.options,
GenericObject.document_xmlid/column3_output/compute_end_usage are all absent
from 0.3.0. pip would resolve that constraint to 0.3.0 and hand someone a
package that dies at import. Their floors move to >=0.4.0 in their own
releases.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Xof4ZUS5n6A5ibX3PXNYbs

Author: pdbethke

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "kirby-cost"
-version = "0.3.0"
+version = "0.4.0"
 description = "Read HERO Designer's own .hdt templates and .hdc characters, and reproduce its point-cost arithmetic exactly."
 readme = { file = "README.md", content-type = "text/markdown" }
 requires-python = ">=3.10"