Fix social.tchncs.de false-positive check (#3111)

Rebased onto latest soxoj/main after #3113. Minimal site-check fix only.

Co-authored-by: juliosuas <juliosuas@users.noreply.github.com>

maigret/resources/data.json

@@ -14283,6 +14283,7 @@
             "regexCheck": "^[a-zA-Z0-9_]+$",
             "urlMain": "https://social.tchncs.de/",
             "url": "https://social.tchncs.de/@{username}",
+            "urlProbe": "https://social.tchncs.de/api/v1/accounts/lookup?acct={username}",
             "usernameClaimed": "Milan",
             "usernameUnclaimed": "noonewouldeverusethis7"
         },

maigret/resources/db_meta.json

@@ -1,8 +1,8 @@
 {
     "version": 1,
-    "updated_at": "2026-09-09T06:17:17Z",
+    "updated_at": "2026-09-09T08:05:35Z",
     "sites_count": 5369,
     "min_maigret_version": "0.5.0",
-    "data_sha256": "e534b34f48b4ef9d391a1766b4bef0d6ffc133f106b22174763266228a8a5f69",
+    "data_sha256": "2318273fdbe0ee7ddd6829758885eb66e4abd4f5e7882644b86d3114c6fe07dc",
     "data_url": "https://raw.githubusercontent.com/soxoj/maigret/main/maigret/resources/data.json"
-}
+}