[Docs] Overhaul Tutorial (#7435)

# Description

Add one end-to-end SO-101 vial-placement tutorial based on the
maintained `IsaacLabTutorial` project while preserving the focused Isaac
Lab mini tutorials.

The new page:

- appears as a standalone **Tutorial** directly below Quickstart
- points to the `IsaacLabTutorial` `main` branch and its maintained
rollout
- explains setup, package discovery, scene and MDP design, reset
curriculum, validation, state-policy training, camera-policy
distillation, evaluation, and extension
- connects the downstream project structure to the Isaac Lab template
generator

The existing mini tutorials remain under the expandable **Tutorials**
entry. The direct-workflow LEAPP tutorial and its annotation
prerequisites are also retained. The deprecated Jetbot walkthrough
remains removed.

No source packages are changed, so no package changelog fragment is
required.

## Type of change

- Documentation update

## Screenshots

The tutorial includes the SO-101 vial-placement rollout and a six-card
navigation menu. The homepage navigation places **Tutorial** below
Quickstart and keeps the mini tutorials under **Tutorials**.

## Validation

- `uv run isaaclab -f`
- `uv run --isolated --extra dev -- make -C docs current-docs`
- Verified rendered navigation and the external `IsaacLabTutorial/main`
rollout URL

## Checklist

- [x] I have read and understood the contribution guidelines
- [x] I have run the pre-commit checks with `uv run isaaclab -f`
- [x] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [x] Tests are not required for this documentation-only change
- [x] No changelog fragment is required because no source package
changed
- [x] My name already exists in `CONTRIBUTORS.md`

## Release backport

- [x] <!-- backport-active-release --> Backport this pull request to the
active release branch after it merges into `develop`

---------

Co-authored-by: Octi Zhang <zhengyuz@nvidia.com>

Author: StafaH

docs/index.rst

@@ -92,6 +92,7 @@ Table of Contents
    source/setup/installation/index
    source/setup/environments
    source/setup/quickstart
+   source/setup/tutorial
    source/migration/migrating_to_isaaclab_3-0
 
 
@@ -112,7 +113,6 @@ Table of Contents
    :caption: Getting Started
    :titlesonly:
 
-   source/setup/walkthrough/index
    source/tutorials/index
    source/how-to/index
    source/overview/developer-guide/index

docs/source/_static/setup/walkthrough_1_1_result.jpg

@@ -68,8 +68,9 @@ For reinforcement learning, much of this has been done for you already! In most
 
 .. seealso::
 
-    We provide a more detailed tutorial for setting up an environment using the manager-based workflow at
-    :ref:`tutorial-create-manager-rl-env`.
+    Start with :ref:`tutorial-create-manager-rl-env` for a focused manager-based environment example. Then follow
+    the :ref:`SO-101 vial-placement tutorial <tutorial-so101-task>` for a complete manipulation task, including its
+    scene, MDP terms, reset curriculum, and agent configuration.
 
 
 Direct Environments
@@ -117,10 +118,9 @@ operations in the environment.
 
 .. seealso::
 
-    We provide a more detailed tutorial for setting up a RL environment using the direct workflow at
+    We provide a detailed tutorial for setting up a direct RL environment at
     :ref:`tutorial-create-direct-rl-env`.
 
-
 .. _IsaacGymEnvs: https://github.com/isaac-sim/IsaacGymEnvs
 .. _OmniIsaacGymEnvs: https://github.com/isaac-sim/OmniIsaacGymEnvs
 .. _Pytorch JIT: https://pytorch.org/docs/stable/jit.html