feat(mubu): add Mubu agent harness

[cnfjlhj]

Description

This PR adds a new cli-anything-mubu harness for the Mubu desktop app.

The harness exposes an agent-oriented CLI with:

• local discovery from backups, RxDB metadata, and sync logs
• live node inspection from the authenticated desktop session
• dry-run-first mutation primitives for update-text, create-child, and delete-node
• a packaged REPL, generated SKILL.md, harness tests, and a CLI-Hub registry entry

Before opening this PR, I tightened the harness for upstream use:

• daily helpers no longer assume a hardcoded personal folder and now require an explicit folder reference or MUBU_DAILY_FOLDER
• packaged docs and generated skill content now use placeholders instead of personal-looking examples
• live E2E checks now skip environment-specific SSL/certificate transport failures instead of reporting harness regressions
• the Mubu harness version and registry entry were bumped to 0.1.1

Since opening the PR, I also hardened the harness against real-world Mubu history edge cases discovered in deeper installed/live testing:

• logical duplicate document paths are now deduplicated by freshest metadata so open-path resolves repeated Mubu history entries predictably
• backup-driven show and links output now overlay document metadata titles and paths instead of leaking root-node titles as document names
• public mubu-cli state now defaults to ~/.config/mubu-cli for new users while preserving fallback to the legacy ~/.config/cli-anything-mubu state dir
• targeted regression tests were added for duplicate document resolution, metadata overlay behavior, and state-dir branding fallback

Type of Change

• New Software CLI — adds a CLI harness for a new application
• Bug Fix — fixes incorrect behavior
• New Feature — adds new functionality to an existing harness or the plugin
• Documentation — updates docs only
• Other — please describe:

---

For New Software CLIs

• MUBU.md SOP document exists at mubu/agent-harness/MUBU.md
• SKILL.md exists inside the Python package (cli_anything/mubu/skills/SKILL.md)
• Unit tests at cli_anything/mubu/tests/test_core.py are present and pass without backend
• E2E tests at cli_anything/mubu/tests/test_full_e2e.py are present
• README.md includes the new software (with link to harness directory)
• registry.json includes an entry for the new software (for the CLI-Hub)
• repl_skin.py in utils/ is an unmodified copy from the plugin

For Existing CLI Modifications

• All unit tests pass: python3 -m pytest cli_anything/mubu/tests/test_core.py -v
• All E2E tests pass: python3 -m pytest cli_anything/mubu/tests/test_full_e2e.py -v
• No test regressions — no previously passing tests were removed or weakened
• registry.json entry is updated if version, description, or requirements changed

General Checklist

• Code follows existing patterns and conventions
• --json flag is supported on any new commands
• Commit messages follow the conventional format (feat:, fix:, docs:, test:)
• I have tested my changes locally

Test Results

cd mubu/agent-harness
python3 -m pytest cli_anything/mubu/tests -q
........................................................................ [ 67%]
.................................                                        [100%]
106 passed in 93.06s

python3 -m unittest cli_anything/mubu/tests/test_agent_harness.py -v
# 11 tests OK