Feature request: handle the same virtual channel (major.minor) on multiple RF channels (translators)

[bleggett29]

Problem
In many markets, translators repeat the same virtual channel number as the main station. In my market (Alamogordo with El Paso / Las Cruces and Albuquerque DMAs) channel 7.1 through 7.x shows up on three different RF channels:

- RF 17: KVIA
- RF 21: KVIA (translator)
- RF 34: KOAT (translator)

All three use 7.1-7.x. When I scan them one after another, each scan overwrites the same GuideNumber entries in lineup.json, so only the last RF channel scanned is left in the lineup. The other two are gone, even though they are different signals (and sometimes different content or a different signal quality).

ATSC 3.0 already avoids this on the 1.0/3.0 split. The same station shows up as 107.1 on ATSC 3.0, so the firmware already knows how to apply an offset to the number.

Proposal
Let the scan keep these as separate lineup entries by applying an offset to the major channel number, for example:

- first RF channel found: 7.1 (no offset)
- second: 207.1
- third: 307.1

Ideally this could be done by:
1. an optional "channel number offset" the user can set per scan or per RF channel (0, 100, 200, 300, ...), and/or
2. automatically adding an offset when a scan finds a GuideNumber that is already in the lineup, instead of overwriting it.

At a minimum, a scan should not silently replace an existing entry that came from a different RF channel.

Why at the hardware level
I can do this today in software, by remapping channels in my DVR software or by tuning directly (RF channel + program). That works, but it means every app has to solve the same problem separately, and apps that just read lineup.json from the device only ever see the last scan. If the device handles it, every client gets the right lineup with no extra work.

Has anyone else run into this? Anyone with translators in their market, or a main station plus a repeater on a different RF channel, probably sees the same thing.

Thanks!
Brian Scott (bleggett29)