vim: Add vim command filename autocomplete (#36332)

Release Notes:

- Adds filename autocomplete for vim commands:
  - write
  - edit
  - split
  - vsplit
  - tabedit
  - tabnew
- Makes command palette interceptor async
<img width="1382" height="634" alt="image"
src="https://github.com/user-attachments/assets/e7bf01c5-e9cd-4a7d-b38c-12fc3df5069f"
/>

---------

Co-authored-by: Conrad Irwin <conrad.irwin@gmail.com>

Cargo.lock

@@ -3755,6 +3755,7 @@ dependencies = [
  "collections",
  "derive_more",
  "gpui",
+ "workspace",
  "workspace-hack",
 ]
 
@@ -18743,6 +18744,7 @@ dependencies = [
  "editor",
  "env_logger 0.11.8",
  "futures 0.3.31",
+ "fuzzy",
  "git_ui",
  "gpui",
  "indoc",