Create placeholder pages for LLM TOC. (#2419)

Summary:


Create the placeholder doc pages following content in [Purpleberry -  Table Of Contents](https://fburl.com/gdoc/ymk7uxm4). 

https://docs-preview.pytorch.org/pytorch/executorch/2419/index.html

Differential Revision: D54878408

Author: Xingying Cheng

docs/source/_templates/layout.html

@@ -62,7 +62,7 @@
 {% block footer %}
 {{ super() }}
 <script script type="text/javascript">
-  var collapsedSections = ['Introduction', 'Getting Started', 'Exporting to ExecuTorch', 'API Reference', 'IR Specification', 'Compiler Entry Points', 'Runtime', 'Quantization', 'Kernel Library', 'Native Delegates', 'SDK', 'Tutorials']
+  var collapsedSections = ['Introduction', 'Getting Started', 'Working with LLMs', 'Exporting to ExecuTorch',  'API Reference', 'IR Specification', 'Compiler Entry Points', 'Runtime', 'Quantization', 'Kernel Library', 'Native Delegates', 'SDK', 'Tutorials']
 </script>
 
 {{ super() }}

docs/source/index.rst

@@ -79,6 +79,17 @@ Topics in this section will help you get started with ExecuTorch.
    getting-started-setup
    runtime-build-and-cross-compilation
 
+.. toctree::
+   :glob:
+   :maxdepth: 2
+   :caption: Working with LLMs
+   :hidden:
+
+   llm/llm-introduction
+   llm/llm-on-mobile/llm-on-mobile
+   llm/llm-on-desktop/llm-on-desktop
+   llm/llm-on-advanced-flow/llm-on-advanced-flow
+
 .. toctree::
    :glob:
    :maxdepth: 1

docs/source/llm/llm-introduction.md

@@ -0,0 +1,7 @@
+# Introduction
+
+## Current landscape of local LLMs
+
+## What is our offering?
+
+## Why and when should you use it?

docs/source/llm/llm-on-advanced-flow/llm-on-advanced-flow.md

@@ -0,0 +1,7 @@
+# Advanced Flows
+
+## Custom quantization
+
+## Bring GGUF to PyTorch ecosystem
+
+## TorchTune interoperability

docs/source/llm/llm-on-advanced-flow/llm-on-advanced-flow.rst

@@ -0,0 +1,9 @@
+Enabling LLMs on Advanced Flow
+=======================
+
+This section will walk you through
+
+.. toctree::
+   :maxdepth: 1
+
+   llm-on-advanced-flow

docs/source/llm/llm-on-desktop/llm-on-desktop-benchmarks.md

@@ -0,0 +1,7 @@
+# Enabling LLMs on Desktop
+
+## Local Llama on Desktop Benchmarks
+
+**Results**
+
+**Instructions**

docs/source/llm/llm-on-desktop/llm-on-desktop.rst

@@ -0,0 +1,9 @@
+Enabling LLMs on Desktop
+=======================
+
+This section will walk you through
+
+.. toctree::
+   :maxdepth: 1
+
+   llm-on-desktop-benchmarks

docs/source/llm/llm-on-mobile/customization-examples.md

@@ -0,0 +1,9 @@
+# Customization examples
+
+## Custom tokenization
+
+## Custom sampler
+
+## Speculative decoding
+
+## Modify a mobile app to use a different LLM model

docs/source/llm/llm-on-mobile/getting-started-with-llms-via-executorch.md

@@ -0,0 +1,16 @@
+# Getting Started with LLMs via ExecuTorch
+
+
+## Simple “Hello World” example
+
+
+## Use Mobile Acceleration
+
+
+## Quantization via XNNPACKQuantizer
+
+
+## Debugging and Profiling
+
+
+## Build Mobile LLM chat App Examples

docs/source/llm/llm-on-mobile/llm-on-mobile-benchmarks.md

@@ -0,0 +1,6 @@
+# Local Llama on Mobile Benchmarks
+
+## Results
+
+
+## Instructions

docs/source/llm/llm-on-mobile/llm-on-mobile.rst

@@ -0,0 +1,12 @@
+Enabling LLMs on Mobile
+=======================
+
+This section will walk you through
+
+.. toctree::
+   :maxdepth: 1
+
+   llm-on-mobile-benchmarks
+   getting-started-with-llms-via-executorch
+   customization-examples
+   validating-other-models

docs/source/llm/llm-on-mobile/validating-other-models.md

@@ -0,0 +1,3 @@
+# Validating other models
+
+## Exportability results