Adds CONF_PCA_PATH + CONF_PCA_KEY config-flow fields. When set, the
coordinator parses programs from the .pca file at that path instead
of streaming them over the wire on every entry refresh. Useful for:
* deployments where wire enumeration is slow (1500-slot iteration)
* offline snapshots when the panel is unreachable
* deterministic test setups against a known fixture
The config-flow validates the file is readable and decrypts cleanly,
surfacing pca_not_found / pca_decode_failed errors via the strings/
en.json translations.
The .pca path is checked first in _discover_programs; if absent the
wire path runs as before. So existing deployments are unaffected.
Tests cover the success path (live fixture, 330 programs) and the
two validation failures (missing file, garbage bytes).
Ryan Malloy
e57fbc41e3