docs: move docs to RunicGateway/docs, repoint all references

Extracted docs/ (ADMIN_CONTROLS, INTEGRATION, PLAN, PROTOCOL_2, RESEARCH,
SHARD_PREREQS) into the central RunicGateway/docs repo under link/, with
full commit history preserved via git filter-repo.

The source cites these design docs by section throughout, so every in-repo
reference (C# + Rust comments, Bridge.cfg, and the READMEs) is repointed at
the new docs-repo URL. README references are rendered as markdown links; a
Documentation pointer section is added to the top-level README.

Docs repo: https://gitea.whitlocktech.com/RunicGateway/docs

overlay/Scripts/Custom/Bridge/BridgeAdmin.cs

@@ -13,7 +13,7 @@ namespace Server.Custom.Bridge
     ///     Every handler runs on the Core thread (BridgeBoot marshals inbound lines through
     ///     Timer.DelayCall first), so they may touch accounts, mobiles, and the network freely.
     ///
-    ///     Trust model (docs/ADMIN_CONTROLS.md §5): authorization is enforced on the *website* —
+    ///     Trust model (https://gitea.whitlocktech.com/RunicGateway/docs/src/branch/main/link/ADMIN_CONTROLS.md §5): authorization is enforced on the *website* —
     ///     these commands are gated there behind admin/moderator roles. The shard trusts the
     ///     loopback socket exactly as town-crier does, and applies inbound commands with an implicit
     ///     CoOwner authority. Its one hard floor is <see cref="Protected"/>: a command refuses any
@@ -248,7 +248,7 @@ namespace Server.Custom.Bridge
         ///     Opens an admin.audit frame (origin=web) with the common fields. Broadcast to every
         ///     connected dashboard so the website's moderation log stays complete regardless of which
         ///     client issued the action. The in-game counterpart (origin=in-game) is emitted from
-        ///     BridgeEvents; see docs/ADMIN_CONTROLS.md §5.5.
+        ///     BridgeEvents; see https://gitea.whitlocktech.com/RunicGateway/docs/src/branch/main/link/ADMIN_CONTROLS.md §5.5.
         /// </summary>
         private static System.Text.StringBuilder AuditBegin(string action, string actor, string target)
         {