[Feature]: Group by test suite title

[binyamin]

🎯 Problem Statement

Currently, the tree view groups by folder name. With nested folders, this can get messy very quickly. It would be helpful if the tests were organized by the name of the suite/test only.

💡 Proposed Solution

Add a config option to switch between grouping by folder & grouping by test/suite title.

🖥️ Your Setup

Item	Value
Operating System	Fedora Linux 44 + Linux 7.1.4
Shell	bash
Project Framework	Node.js
Test Framework	node:test
Project Type	lib/module
IDE	VSCode
VSCode Version	1.130.0
Extension Version	0.4.148

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📸 Screenshots or Examples

Instead of showing 7 levels...

example

• src
  • lib
    • utils
      • foo.test.ts
        • foo()
          • test 1
          • test 2
    • engine
      • bar-a.test.ts
        • bar()
          • test 1
            • suite 1
              • test 1
      • bar-b-test.ts
        • bar()
          • suite 2
            • test 1

...just show 3 levels.

example

• foo()
  • test 1
  • test 2
• bar()
  • test 1
  • suite 1
    • test 1
  • suite 2
    • test 1

For context, here is the imaginary file tree:

src/
├── cli/
└── lib/
    ├── utils/
    │   ├── foo.ts
    │   └── foo.test.s
    └── engine/
        ├── bar.ts
        ├── bar-a.test.ts
        ├── bar-b.test.ts
        └── bar-c.test.ts

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💡 Additional Context

Related to #462