docs(questions): v4 badge doorman modernization round [#345]

Opens the actuator/reader-format/whitelist questions for the badge
system modernization on #345/#355.

Findings note: https://projects.knownelement.com/issues/355#note-3955

questions-v4.md

@@ -0,0 +1,28 @@
+# Questions — v4 (current round)
+
+Round v3 closed 2026-09-02 with no open repo-local questions.
+This round opens 2026-09-02 for the badge doorman modernization.
+
+## Badge doorman modernization (#345 / #355 / #356)
+
+**Q1. Door actuator path?** The 2018 `doorman.pl` fired a `usbrelay`
+(device 3X9XI_1) door strike from the reader host. Is that still the
+hardware on the server-room door, or does the new e-lock (Fri 09-04
+onsite batch) take over the strike? If e-lock: make/protocol
+(Zigbee / Z-Wave / HomeKit / wired)? This decides whether HA unlocks
+natively or the pfvsvrpi listener drives the relay on HA's behalf.
+**A:**
+
+**Q2. Reader model + badge format?** Old reader was a keyboard-emulating
+USB RFID reader (usb-13ba "Barcode_Reader"), 10-digit raw-decimal IDs.
+From the box with a reader at fingertips (ultix-field is live in San
+Antonio): paste `lsusb` and `ls -l /dev/input/by-id/` output — and if
+convenient, one badge scan captured with `evtest`.
+**A:**
+
+**Q3. Badge whitelist home?** Proposal: the whitelist lives in HA
+(pfv-bms package: badge_id → identity), replacing the defunct
+doors.pfv.turnsys.net portal and the hardcoded backdoor list. The two
+legacy 2018 badge IDs (Charles NW / Josef C) get re-enrolled through the
+new path, never hardcoded again. Confirm?
+**A:**