Wraps the Akaunting Double-Entry module so `akt` can drive the general ledger (closes #5).
New resources
- `journal-entry` (full CRUD via `/api`) — balanced multi-line entries with a client-side debit==credit guard (≥2 lines) before any network call, auto-generated `journal_number`, and ledger-preserving updates (existing lines resent with their ids so a scalar-only update doesn't wipe the entry).
- `chart-of-account` — `list`/`get` via `/api`; `create`/`update`/`delete` via the session/CSRF web route (the module publishes accounts read-only on `/api`), including sub-accounts via `--account-id`.
Client
- New `web_json()` for session-authenticated web-surface calls that unwrap Akaunting's `{success,error,data,message}` AJAX envelope. CSRF flows via the `X-XSRF-TOKEN` header (echoing the encrypted `XSRF-TOKEN` cookie, which Laravel decrypts) — the same mechanism Akaunting's axios frontend uses.
Verified end-to-end against the live instance. Adds 9 unit tests plus integration coverage that skips gracefully when the module isn't installed.