Traverse Project file path to find .AmazonQ folder for rules

## Problem
We have larger repos with many different folders where we would open up with VS Code. Currently, Q will only look in the project folder which means would have to duplicate some of system wide rules. This makes management and maintenance difficult.

## Expected behavior
We would like to be able to put the .amazonQ folder at the root of the repo so that we can define our rules in a single location. The extension should traverse the project path and accumulate all rules.

Start by locating the TypeScript code that discovers the current project folder's .amazonQ rules, then trace how the VS Code project path is represented. The work is done when nested project openings find a repository-root .amazonQ folder and accumulate its rules with the existing project rules.

Written by the indexing model from the issue text.