[move-ide] Added support for enums (#18124)

## Description 

This PR adds enums support to the Move analyzer. 

In this PR, I also sneaked a fix for symbols merging, which was not very
robust when multiple packages are built within the same IDE instance.
It's much more robust to keep symbols on the per-package basis, even if
it's more memory-intensive.

## Test plan 

All existing and newly added tests must pass.

external-crates/move/crates/move-analyzer/editors/code/README.md

@@ -82,6 +82,7 @@ Move source file (a file with a `.move` file extension) and:
 - Place your cursor on a delimiter, such as `<`, `(`, or `{`, and its corresponding delimiter --
   `>`, `)`, or `}` -- will be highlighted.
 - As you type, the editor will offer completion suggestions, in particular:
+  - struct field name and method name suggestions following `.` being typed
   - code snippets to complete `init` function and object type definitions
 - If the opened Move source file is located within a buildable project (a `Move.toml` file can be
   found in one of its parent directories), the following advanced features will also be available:

external-crates/move/crates/move-analyzer/editors/code/package.json

@@ -5,7 +5,7 @@
   "publisher": "mysten",
   "icon": "images/move.png",
   "license": "Apache-2.0",
-  "version": "1.0.5",
+  "version": "1.0.6",
   "preview": true,
   "repository": {
     "url": "https://github.com/MystenLabs/sui.git",