feat(lists): expose emoji + color in get_lists + create_list (v0.5.1)

get_lists now includes emoji and color fields per list entry.
create_list response also returns emoji and color from the API.

Field name verification (FW_DEBUG=1, 2026-04-16):
- emoji: API returns "" when unset -> normalised to null
- color: API omits key when unset -> normalised to null
- Both fields present in taskgettasklists and taskcreatelist responses

SPEC.md: taskgettasklists documented with full response structure
         and emoji/color normalisation notes.
         taskcreatelist response updated with emoji + color fields.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "mcp-familywall"
-version = "0.4.16"
+version = "0.5.1"
 description = "MCP server for Family Wall — read your family's lists and tasks via Claude"
 readme = "README.md"
 requires-python = ">=3.12"