Replace # with - in Zabbix host names (Zabbix 7.x compatibility)

Zabbix 7.x rejects '#' in host names. Changed hostname format from
'yodeck#<id>' to 'yodeck-<id>' (e.g. yodeck-54239).
Updated SNMP col 1 value and docs for consistency.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

snmp_test.py

@@ -25,7 +25,7 @@ from app.config import DB_PATH, ENTERPRISE_OID
 from app.database import get_all_players, get_player_counts
 
 COLUMNS = [
-    (1, 'STRING',  'hostname',   lambda p: f"yodeck#{p['id']}"),
+    (1, 'STRING',  'hostname',   lambda p: f"yodeck-{p['id']}"),
     (2, 'STRING',  'name',       lambda p: p.get('name') or ''),
     (3, 'INTEGER', 'online',     lambda p: str(p.get('online', 0))),
     (4, 'STRING',  'last_seen',  lambda p: p.get('last_seen') or ''),
@@ -62,7 +62,7 @@ def main():
 
     for p in players:
         pid = p['id']
-        print(f"  -- yodeck#{pid}  ({p['name']})")
+        print(f"  -- yodeck-{pid}  ({p['name']})")
         for col, typ, label, getter in COLUMNS:
             oid = f".{base}.{col}.{pid}"
             val = getter(p)