Normalize T6 hexadecimal RCON GUIDs for ping matching

tests/unit/server-observation.test.ts

@@ -115,6 +115,44 @@ describe('shared server observation', () => {
         expect(selectServerObservation(server({ rcon_status: { ...raw, last_seen_at: at(-90_001) } }), telemetry, now).roster?.map(player => player.ping)).toEqual([null, null]);
     });
 
+    it.each([
+        ['6C4C20', '7097376'], ['6c45dd', '7095773'], ['00006C4C20', '0007097376'],
+        ['0x6C45DD', '7095773'], ['10', '16'], ['20000000000001', '9007199254740993']
+    ])('matches T6 hex GUID %s to decimal %s despite different names', (hex, decimal) => {
+        const telemetry = report(0, 1);
+        telemetry.players[0].guid = decimal;
+        const raw = server({ roster: [{ num: 0, score: 100, ping: 91, guid: hex, name: 'Previous name' }] });
+        const selected = selectServerObservation(server({ game: 't6', rcon_status: raw }), telemetry, now);
+        expect(selected.roster?.[0]).toMatchObject({ guid: decimal, name: 'Player 1', ping: 91, score: 5000 });
+        expect(selected.rcon_status?.roster?.[0].guid).toBe(hex);
+    });
+
+    it.each(['t5', undefined])('keeps decimal-looking GUIDs literal for game %s', game => {
+        const telemetry = report(0, 2);
+        telemetry.players[0].guid = '10';
+        telemetry.players[1].guid = '16';
+        const raw = server({ roster: [{ num: 0, score: 100, ping: 91, guid: '10', name: 'Previous name' }] });
+        expect(selectServerObservation(server({ game, rcon_status: raw }), telemetry, now).roster?.map(player => player.ping)).toEqual([91, null]);
+    });
+
+    it('treats digit-only T6 GUIDs as hexadecimal and reserves normalized matches before names', () => {
+        const telemetry = report(0, 2);
+        telemetry.players[0].guid = '10';
+        telemetry.players[1].guid = '16';
+        const raw = server({ roster: [{ num: 0, score: 100, ping: 91, guid: '10', name: 'Player 1' }] });
+        expect(selectServerObservation(server({ game: 't6', rcon_status: raw }), telemetry, now).roster?.map(player => player.ping)).toEqual([null, 91]);
+    });
+
+    it('rejects duplicate RCON GUIDs after normalization without bypassing them by name', () => {
+        const telemetry = report(0, 1);
+        telemetry.players[0].guid = '7097376';
+        const raw = server({ roster: [
+            { num: 0, score: 100, ping: 91, guid: '6C4C20', name: 'Player 1' },
+            { num: 1, score: 100, ping: 42, guid: '006c4c20', name: 'Other player' }
+        ] });
+        expect(selectServerObservation(server({ game: 't6', rcon_status: raw }), telemetry, now).roster?.[0].ping).toBeNull();
+    });
+
     it.each(['rcon', 'telemetry', 'case', 'blank', 'invalid-ping'])('rejects ambiguous or invalid %s name fallback', mode => {
         const telemetry = report(0, 2);
         const player = { num: 0, score: 100, ping: 42, guid: 'different-guid', name: telemetry.players[0].name };