fix(amazonq): "rejectCodeSuggestion not found" after ctrl-z aws#5482

Problem:
"aws.amazonq.rejectCodeSuggestion not found" error by doing below steps:
1. Install VSCodeVim
2. Trigger a code suggestion from Amazon Q.
3. Press tab to accept it.
4. Press Ctrl + Z to revoke the acceptance, then you will see the inline suggestion shown again. 
5. Press Esc to reject it, then you will see `aws.amazonq.rejectCodeSuggestion` not found. 

In fact this is reproducible even without Vim. The root cause is the `Ctrl + Z`
reverted the editor states and brought back the inline suggestions while the
command override subscriptions were not brought back.

During testing, I reproduced the `crashing` issue using Vim. 
1. Install VSCodeVim.
2. Trigger a Q suggestion.
3. Press left or right arrow, then the suggestion does not navigate to next,
   previous suggestion, instead the cursor moves. After this, I am not getting
   code suggestions unless after sometime or certain conditions. 

The root cause to this is: Vim override the left right keybindings
https://github.com/VSCodeVim/Vim/blob/89cf2d0356966303dc1bac7ce40eaef167d44088/package.json#L123
The keybinding override was somehow ranked as a higher priority item than Q left
right navigation buttons. 

Before the fix, you can change the keybinding of
`editor.action.inlineSuggest.showNext` to something not like right arrow key to
avoid such keybinding conflict. You can also change keybinding of
`extension.vim_right` (when VSCodeVim is installed) to avoid such conflict which
caused crashing . I was able to make Q working after fixing these keybinding
conflict.

Solution:

Test case 1: Trigger suggestion, accept it, ctrl +z, saw same
suggestion, press Esc, suggestion disappears. The error command not
found is not thrown. In this case, user can also reject it by keep
typing to ignore it.

Test case 2: Install Vim. Trigger suggestion, accept it, ctrl +z, saw
same suggestion, press Esc, suggestion disappears. The error command not
found is not thrown. In this case, user can also reject it by keep
typing to ignore it. .

Test case 3: Install Vim. Trigger suggestion, press left or right, the
navigation is still not working(because Vim overrides the left right
keys with highest priority), however, there is no crash anymore and user
can still accept or reject the inline suggestion.

Test case 4: Install Q and other code suggestion extensions, with this
change, the key bindings are always under our extension, so when their
suggestion shows, it triggers our command which breaks their experience.

Author: leigaol

packages/amazonq/.changes/next-release/Bug Fix-43d1cc50-8f12-4467-9331-f9b1fe89381d.json

@@ -0,0 +1,4 @@
+{
+	"type": "Bug Fix",
+	"description": "Fix bug when undo inline suggestion causes command not found"
+}

packages/core/src/codewhisperer/activation.ts

@@ -454,6 +454,7 @@ export async function activate(context: ExtContext): Promise<void> {
     }
 
     async function setSubscriptionsforInlineCompletion() {
+        RecommendationHandler.instance.subscribeSuggestionCommands()
         /**
          * Automated trigger
          */

packages/core/src/codewhisperer/service/recommendationHandler.ts

@@ -59,8 +59,10 @@ const nextCommand = Commands.declare('editor.action.inlineSuggest.showNext', ()
 })
 
 const rejectCommand = Commands.declare('aws.amazonq.rejectCodeSuggestion', () => async () => {
+    if (!isCloud9('any')) {
+        await vscode.commands.executeCommand('editor.action.inlineSuggest.hide')
+    }
     RecommendationHandler.instance.reportUserDecisions(-1)
-
     await Commands.tryExecute('aws.amazonq.refreshAnnotation')
 })
 
@@ -455,7 +457,6 @@ export class RecommendationHandler {
             this.clearRecommendations()
             this.disposeInlineCompletion()
             await vscode.commands.executeCommand('aws.amazonq.refreshStatusBar')
-            this.disposeCommandOverrides()
             // fix a regression that requires user to hit Esc twice to clear inline ghost text
             // because disposing a provider does not clear the UX
             if (isVscHavingRegressionInlineCompletionApi()) {
@@ -668,8 +669,6 @@ export class RecommendationHandler {
             })
             this.reportUserDecisions(-1)
         } else if (session.recommendations.length > 0) {
-            this.subscribeSuggestionCommands()
-            // await this.startRejectionTimer(editor)
             await this.showRecommendation(0, true)
         }
     }