NEP: feature flag & bug fix (aws#7410)

1. Added a feature flag `amazonqLSPNEP` for NEP.
Configure the settings.json like:
```
"aws.experiments": {
        "amazonqLSP": true,
        "amazonqLSPInline": true, // optional: enables inline completion from flare
        "amazonqLSPChat": true, // optional: enables chat from flare
        "amazonqLSPNEP": true, // optional: enables next edit prediction
    },
```
2. Fixed some UI/UX bugs:
- Color theme matches IDE light/dark theme
- Cursor move to the end of edit once accepted
- Added conditions to the accept/reject commands so tab/esc works
outside of NEP context.

---

- Treat all work as PUBLIC. Private `feature/x` branches will not be
squash-merged at release time.
- Your code changes must meet the guidelines in
[CONTRIBUTING.md](https://github.com/aws/aws-toolkit-vscode/blob/master/CONTRIBUTING.md#guidelines).
- License: I confirm that my contribution is made under the terms of the
Apache 2.0 license.

---------

Co-authored-by: aws-toolkit-automation <>
Co-authored-by: atontb <104926752+atonaamz@users.noreply.github.com>
Co-authored-by: 🥩 Flora <floralph@amazon.com>

Author: 3 people

packages/amazonq/src/app/inline/EditRendering/displayImage.ts

@@ -3,7 +3,6 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-import { getLogger, setContext } from 'aws-core-vscode/shared'
 import { getLogger, setContext } from 'aws-core-vscode/shared'
 import * as vscode from 'vscode'
 import { diffLines } from 'diff'
@@ -291,22 +290,13 @@ export async function displaySvgDecoration(
             // Handle accept
             getLogger().info('Edit suggestion accepted')
 
-            // Replace content
-
-            // Calculate cursor position before replacing content
-            const endPosition = getEndOfEditPosition(originalCode, newCode)
-
             // Replace content
             replaceEditorContent(editor, newCode)
 
             // Move cursor to end of the actual changed content
             const endPosition = getEndOfEditPosition(originalCode, newCode)
             editor.selection = new vscode.Selection(endPosition, endPosition)
 
-            // Move cursor to end of the actual changed content
-            editor.selection = new vscode.Selection(endPosition, endPosition)
-
-
             // Move cursor to end of the actual changed content
             editor.selection = new vscode.Selection(endPosition, endPosition)