NTFS load order, a title-sorted AddOns list, and tooltips at the cursor

- addons load in the order NTFS lists a folder, case-insensitive with an underscore before the letters, the order the vanilla corpus was written against and the one that decides which addon provides a shared library (2178)
- GetNumAddOns and the index form of every AddOn verb walk a title-sorted list that hides the Blizzard addons the server says to hide, and the character-select AddOns list is in title order (2175)
- SetPoint and SetAllPoints raise the reference's own errors for a frame name that does not exist or an omitted relative frame instead of quietly anchoring to the parent, and an explicit nil means the screen root (2176)
- a tooltip owned with ANCHOR_CURSOR follows the mouse, which pfUI's tooltip, xpbar and chat modules, pfQuest's browser and TipBuddy ask for; an omitted or unknown anchor is ANCHOR_LEFT (2176)
- a $parent name handed to CreateFrame, CreateTexture or CreateFontString expands as it does in XML, so FonzAppraiser's thirty dropdowns and pfQuest's search icon get the names they asked for (2176)

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

crates/benilla-protocol/src/messages/opcode.rs

@@ -90,6 +90,9 @@ pub const SMSG_AUTH_RESPONSE: u16 = 0x01EE;
 /// in the world. benilla does not implement Warden; [`crate::WorldSession::connect`] refuses such
 /// a server at the handshake rather than entering a 30-second kick/reconnect cycle.
 pub const SMSG_WARDEN_DATA: u16 = 0x02E6;
+/// The server's answer to `CMSG_AUTH_SESSION`'s addon block — one record per `## Secure:` addon we
+/// sent, in the order we sent them, with no count and no names (decision 2175).
+pub const SMSG_ADDON_INFO: u16 = 0x02EF;
 pub const SMSG_COMPRESSED_UPDATE_OBJECT: u16 = 0x01F6;
 /// A zlib envelope holding a **batch of whole movement packets** (763, VERIFIED vmangos
 /// `Opcodes_1_12_1.h`). Not an edge case: vmangos moves a session onto this carrier the moment it