Reorganize code into mindmap and worklog packages

Add CLAUDE.md with development guidelines

Extract value objects for ORGMode date reading logic

Create goal to install and init

Add Ruff: checker + linter + pre-commit config

Export ORGMode: all projects + project in TIMES (#8)

document freeplane and freemind

refactor: rename print_as_titles to titles

refactor: rename mindmap_orgmode_lists to orgmode_lists

refactor: rename mindmap_orgmode to orgmode

Add --output argument for file output support

Remove StringIO from tests, use parse() and format() directly

Refactor all formatters to use parse-then-print interface

Refactor mindmap_orgmode_lists to use parse-then-print interface

Exporter: orgmode lists (#6)