fix(tabs): rehydrate pinned TempTab tell-targets after reload

Smoke-test (Jin's scenario) surfaced two coupled bugs in v1.4.7 pin
persistence:

1. The chat input couldn't send to the pinned partner after a reload.
   Tab.CurrentChannel is NonSerialized, so it came back as a fresh
   UsedChannel with TellTarget=null even though tab.TellTarget (the
   persisted twin) was intact. The game-side channel hook only repaints
   CurrentChannel on a /tell or channel switch, so the pinned tab sat
   there mute until the user manually re-bounced the channel.

2. An incoming tell from the pinned partner spawned a *second* TempTab
   instead of routing into the existing pinned one. The Name+World
   lookup in FindTempTab was vulnerable to any round-trip nuance on
   tab.TellTarget — the fallback path now matches by tab name, which
   FormatTabName pins at spawn time.

Fix:
- AutoTellTabsService.Initialize now calls RehydratePinnedTabs() after
  the Phase-2 wiring lands, seeding tab.CurrentChannel.TellTarget +
  Channel from the persisted tab.TellTarget. Channel is also defaulted
  to InputChannel.Tell on the tab record so the chat-input bar paints
  Tell mode immediately on first selection.
- FindTempTab gained a Name-based fallback for the case where the
  primary TellTarget lookup misses (e.g. a pinned tab whose TellTarget
  didn't round-trip cleanly through an old save).
- HandleTell self-heals: when the fallback matches a pinned tab with a
  missing TellTarget, the tab is repaired from the live partner data
  and persisted, so subsequent messages take the fast path.

Build-suite coverage was attempted (PinnedTabJsonRoundtripTests) but
Tab + TellTarget are both Dalamud-coupled — Newtonsoft's reflection
walk loads Dalamud.dll which isn't available in the xUnit AppDomain
(documented in feedback_dalamud_test_isolation). Verification stays on
the ingame smoke path.

HellionChat/AutoTellTabsService.cs

@@ -52,11 +52,33 @@ internal sealed class AutoTellTabsService : IDisposable
             return;
         }
 
+        // Pinned tabs come out of the JSON with TellTarget set but
+        // CurrentChannel reset (NonSerialized). Without re-seeding, the chat
+        // input has no tell-target on the active pinned tab, and the
+        // game-side channel hook only repaints CurrentChannel once the user
+        // triggers a /tell or channel switch.
+        RehydratePinnedTabs();
+
         _messageManager.MessageProcessed += HandleTell;
         Plugin.ClientState.Logout += OnLogout;
         _initialized = true;
     }
 
+    private static void RehydratePinnedTabs()
+    {
+        foreach (var tab in Plugin.Config.Tabs)
+        {
+            if (!TabLifecycleHelpers.IsInPinnedPool(tab))
+                continue;
+            if (tab.TellTarget is null || !tab.TellTarget.IsSet())
+                continue;
+
+            tab.Channel ??= InputChannel.Tell;
+            tab.CurrentChannel.Channel = InputChannel.Tell;
+            tab.CurrentChannel.TellTarget = tab.TellTarget.Clone();
+        }
+    }
+
     public void Dispose()
     {
         if (!_initialized)
@@ -102,7 +124,23 @@ internal sealed class AutoTellTabsService : IDisposable
             var existing = FindTempTab(partner.Value.Name, partner.Value.World);
             if (existing != null)
             {
-                // Already routed via MessageManager pipeline
+                // Already routed via MessageManager pipeline. Repair the
+                // tell-target if the fallback hit a pinned tab whose
+                // TellTarget didn't survive a previous round-trip — keeps
+                // FindTempTab fast on the next message.
+                if (
+                    existing.IsPinned
+                    && (existing.TellTarget is null || !existing.TellTarget.IsSet())
+                )
+                {
+                    existing.TellTarget = new TellTarget(
+                        partner.Value.Name,
+                        partner.Value.World,
+                        0,
+                        TellReason.Direct
+                    );
+                    _plugin.SaveConfig();
+                }
                 return;
             }
 
@@ -152,14 +190,25 @@ internal sealed class AutoTellTabsService : IDisposable
         return null;
     }
 
-    private Tab? FindTempTab(string name, uint world)
+    private static Tab? FindTempTab(string name, uint world)
     {
-        return Plugin.Config.Tabs.FirstOrDefault(t =>
+        var byTarget = Plugin.Config.Tabs.FirstOrDefault(t =>
             t.IsTempTab
             && t.TellTarget != null
             && string.Equals(t.TellTarget.Name, name, StringComparison.OrdinalIgnoreCase)
             && t.TellTarget.World == world
         );
+        if (byTarget != null)
+            return byTarget;
+
+        // Fallback: match by tab name. Pinned tabs are named via
+        // FormatTabName(player, world) at spawn time, so the name is a
+        // stable secondary key when TellTarget didn't survive a save/load
+        // (older configs from a renamed pin, malformed migrations, etc.).
+        var expectedName = FormatTabName(name, world);
+        return Plugin.Config.Tabs.FirstOrDefault(t =>
+            t.IsTempTab && string.Equals(t.Name, expectedName, StringComparison.OrdinalIgnoreCase)
+        );
     }
 
     internal void DropOldestTempTab()