Add contact name resolution from macOS AddressBook

- Copy contacts.rs from imessage-exporter (GPL-3.0 compatible)
- Build ContactsIndex from ~/Library/Application Support/AddressBook/
- Resolve phone/email to first/last names for 1:1 chats
- Handle::cache + dedupe for participant mapping
- Test shows 586 contacts loaded, 18 participants resolved

Example output now shows "Tim Muhundan" instead of "+64210323287"

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: ndbroadbent

src-tauri/Cargo.lock

@@ -21,7 +21,8 @@ anyhow = "1"
 thiserror = "2"
 
 # iMessage database access - the core functionality
-imessage-database = "2"
+imessage-database = "3"
+rusqlite = "0.37"
 
 [features]
 default = ["custom-protocol"]