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/pass_persist.py

@@ -5,7 +5,7 @@ net-snmp pass_persist handler for Yodmon.
 Reads player data from the SQLite database and serves it over SNMP v2c.
 
 OID layout  (base = ENTERPRISE_OID.1.1):
-  base.1.<yodeck_id>  STRING   "yodeck#<id>"
+  base.1.<yodeck_id>  STRING   "yodeck-<id>"
   base.2.<yodeck_id>  STRING   player display name
   base.3.<yodeck_id>  INTEGER  online     (1 = online, 0 = offline)
   base.4.<yodeck_id>  STRING   last_seen  (ISO-8601 timestamp)
@@ -27,7 +27,7 @@ BASE_OID       = f"{ENTERPRISE_OID}.1.1"
 
 # (column_index, snmp_type, value_extractor)
 COLUMNS = [
-    (1, 'STRING',  lambda p: f"yodeck#{p['id']}"),
+    (1, 'STRING',  lambda p: f"yodeck-{p['id']}"),
     (2, 'STRING',  lambda p: p.get('name') or ''),
     (3, 'INTEGER', lambda p: str(p.get('online', 0))),
     (4, 'STRING',  lambda p: p.get('last_seen') or ''),