Repo plan + naming (Go/TS/Py)

## Goal
Finalize repo names and responsibilities.

## Proposed
- finulio-sdk-go (or finulio-snapshotdiff)
- finulio-sdk-js
- finulio-tools-py

## Rule
Schemas only from finulio-schemas release/tags (no duplication).

## Done when
- Names agreed + repos created + README stubs
