chore: Bump version to 0.46.0

Updated all component versions:
- bd CLI: 0.45.0 → 0.46.0
- Plugin: 0.45.0 → 0.46.0
- MCP server: 0.45.0 → 0.46.0
- npm package: 0.45.0 → 0.46.0
- Documentation: 0.45.0 → 0.46.0

Changes in 0.46.0:
- Custom type support in beads config.yaml (bd-649s)
- Gas Town types extraction into beads core (bd-i54l)
- Gate workflow discovery improvements (bd-m8ew)

cmd/bd/templates/hooks/pre-push

@@ -1,6 +1,6 @@
 #!/usr/bin/env sh
 # bd-shim v1
-# bd-hooks-version: 0.45.0
+# bd-hooks-version: 0.46.0
 #
 # bd (beads) pre-push hook - thin shim
 #