Map shows "faction_camp" label intermittently

### Describe the bug

When looking around the map, I see a "faction_camp" label intermittently overlaid over an actual faction's base, and the specific tiles that trigger this behavior change at different zoom levels.

### Attach save file

[Hunt-trimmed.tar.gz](https://github.com/user-attachments/files/21536252/Hunt-trimmed.tar.gz)

### Steps to reproduce

1. Open the map in the attached save
2. Move the cursor around and look near the northern Isherwood Stables label
3. See a "faction_camp" label appear and disappear as the cursor moves
4. Zoom in or out
5. Move the cursor around
6. See the erroneous label for a different set of cursor locations

### Expected behavior

No such label

### Screenshots

### Versions and configuration

- OS: Linux
- OS Version: LSB Version: n/a; Distributor ID: EndeavourOS; Description: EndeavourOS Linux; Release: rolling; Codename: rolling;
- Game Version: 4ba607529f-dirty [64-bit]
- Graphics Version: Tiles
- Game Language: System language []
- Mods loaded: [
Dark Days Ahead [dda],
Disable NPC Needs [no_npc_food],
Portal Storms Ignore NPCs [personal_portal_storms],
Alternative Map Key [alt_map_key],
Generic Guns [generic_guns]
]

### Additional context

In the screenshot, I started at the southern extent of the problem and started marking tiles as `E`xplored to indicate which ones trigger the bug. The gaps show the intermittent nature of the problem. I didn't make it all the way up to the Isherwood labels or beyond because I noticed the zoom inconsistency.

Use the attached save file to reproduce the map behavior near the northern Isherwood Stables label. Test cursor movement and multiple zoom levels, then identify why the faction_camp label appears over the faction base. Done means the erroneous label no longer appears at any tested cursor location or zoom level.

Written by the indexing model from the issue text.