feat(inline completion): enhance inline completion context fetching (aws#6356)

## Problem
corresponding JB change
aws/aws-toolkit-jetbrains#5256 (vscode logics
has been implemented)



## Solution


---

- 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.

Author: Will-ShaoHua

packages/amazonq/.changes/next-release/Feature-d0329e3d-65bd-4987-b87c-ee11b86de399.json

@@ -0,0 +1,4 @@
+{
+	"type": "Feature",
+	"description": "Enhance Q inline completion context fetching for better suggestion quality"
+}