vscode: Configure breadcrumbs to work like vim-vinegar

I've been using Vim for a while now and I'm trying out Visual Studio
Code. One thing I have been missing a lot is the ability to navigate
between files in the way that vim-vinegar enables.

Using this plugin in Vim, I can press - and be taken into a file
browser, starting in the directory that the current file is in.
Selecting a file opens it, and pressing - again traverses up a directory
level.

https://stackoverflow.com/questions/54834068/replacement-for-vim-vinegar-in-vs-code

I think I can replicate the experience I want using breadcrumbs. This
commit represents my first attempt at this by:

- enabling breadcrumbs
- adding a vim normal mode keybinding of `-` to enable and focus
  breadcrumbs
- adding a keyboard shortcut of `-` while breadcrumbs are visible to
  navigate "up a level"

This isn't perfect yet, specifically pressing enter on a directory does
nothing, but it is a big step in the right direction.

vscode/keybindings.json

@@ -3,4 +3,11 @@
 
   // From https://code.visualstudio.com/docs/getstarted/userinterface#_working-without-tabs
   { "key": "cmd+w", "command": "workbench.action.closeEditorsInGroup" },
+
+  // Make breadcrumbs work more like vim-vinegar
+  {
+    "key": "-",
+    "command": "breadcrumbs.focusPrevious",
+    "when": "breadcrumbsActive && breadcrumbsVisible",
+  },
 ]

vscode/settings.json

@@ -1,4 +1,6 @@
 {
+  "breadcrumbs.enabled": true,
+
   // Prevent typing things like `.` and `;` from accepting autocomplete suggestions
   "editor.acceptSuggestionOnCommitCharacter": false,
 
@@ -134,7 +136,22 @@
           "args": []
         }
       ]
-    }
+    },
+
+    // vim-vinegar
+    {
+      "before": ["-"],
+      "commands": [
+        {
+          "command": "breadcrumbs.toggleToOn",
+          "when": "!config.breadcrumbs.enabled",
+        },
+        {
+          "command": "breadcrumbs.focusAndSelect",
+          "when": "breadcrumbsPossible",
+        },
+      ],
+    },
   ],
 
   /*