[Alts] Server-side search controls, IP counts, adjustable window (#7517)

* [Alts] Server-side search controls, IP counts, adjustable window

Plumbs the match-type chips through to the server: include_email/include_clientid/include_ip skip disabled identifier types in both matching and frontier expansion, so excluded types (e.g. throwaway domains) never enter the graph at any depth. Session lookback becomes adjustable (session_months, clamped 1-24, default 6). Each alt row carries ip_count, the distinct recent session IP count shown in a new IPs column. All proto additions are optional with old defaults, so old clients/servers interoperate.

* Fix remaining review threads on the alts search controls

- Disable keyboard tracking on the depth and window spin boxes so typing a
  two-digit value sends one search, not one per digit.
- Reload the user under investigation on a filter change instead of reading
  the search box, which could switch to a name never submitted.
- Keep a chip's last match count while it is unchecked; the server omits
  unchecked match types, so the label used to drop to "(0)".

---------

Co-authored-by: Lukas Brübach <Bruebach.Lukas@bdosecurity.de>

servatrice/src/servatrice_database_interface.h

@@ -224,7 +224,12 @@ public:
                                                        const QString &beforeTime = QString(),
                                                        bool *hasMore = nullptr);
     QList<ServerInfo_UserSession> getUserSessions(const QString &userName, int limit);
-    QList<ServerInfo_UserAlt> getUserAlts(const QString &userName, int depth = 1);
+    QList<ServerInfo_UserAlt> getUserAlts(const QString &userName,
+                                          int depth = 1,
+                                          bool useEmail = true,
+                                          bool useClientId = true,
+                                          bool useIp = true,
+                                          int sessionMonths = 6);
     QList<ServerInfo_ModeratorLogin> getModeratorLastLogins();
 
     // Uptime snapshot as recorded by Servatrice::statusUpdate() into the