ESPHome web_server Plaintext Password Disclosure via JSON "value" Field

ESPHome through 2026.7.0-dev discloses plaintext passwords via its web_server component. In WebServer::text_json_() (esphome/components/web_server/web_server.cpp), a text entity configured with mode: password (TEXT_MODE_PASSWORD) has its JSON "state" field correctly masked as "********", but the same serialization path unconditionally writes the raw password into the JSON "value" field via set_json_icon_state_value()/set_json_value(). Because web_server listens on port 80 with no authentication by default, any attacker on the local network can retrieve the plaintext password (e.g. WiFi credentials, API tokens) via GET /text/<entity_id> or the /events EventSource stream.