[citoki]

What

A second data source next to MQTT: with source: vaillant_ebus the card reads and writes the time programs through the
Vaillant eBUS integration, which talks to ebusd over TCP. No MQTT and no
sensor per slot needed.

type: custom:ebusd-time-program-card
source: vaillant_ebus
programs: [z1, hwc, cc]

Depends on MarkBovee/vaillant-ebus#229, which adds the read_time_program and write_time_program actions. Until
that is released, source: vaillant_ebus shows "not found" with a hint; the MQTT source (default) is unchanged.

How

• New options source (mqtt | vaillant_ebus), refresh_interval (default 300 s, reads from ebusd's cache) and
  entry_id (only with several integration entries).
• src/adapters/vaillant-ebus.ts: calls the actions with returnResponse; one shared read per program for all cards
  on the page; a failed read keeps the last values (offline) and is retried after 30 s.
• Write job: a day can be written by an action that reads it back itself. Retry, continue and restore work as before.
• The set-back temperature needs setback_entity with this source (no MQTT write).
• Dev page: ?source=vaillant_ebus uses a fake integration in test/fake-ebusd.ts.
• Three new texts in all 14 languages; docs/options.md has a new "Source" section.

Tests

• npm test: 168 tests (17 new), npm run typecheck clean.
• npm run test:e2e: all 9 checks, 2 new for the vaillant_ebus source (write, and a day the controller ignores).
• Live: local Home Assistant dev instance with the integration from the PR above, against the production ebusd
  (CTLV2 SW0514). Read and write worked; the MQTT card on the production system showed the changes shortly after.