Add issue templates and deprecation warning to the book

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,31 @@
+---
+name: Bug report
+about: Create a report to help us improve
+title: ''
+labels: ["bug", "bug jury"]
+assignees: ''
+
+---
+
+## Bug description
+
+<!-- A clear and concise description of what the bug is. -->
+
+## To Reproduce
+
+<!-- Steps to reproduce the behavior. -->
+1. ...
+2. ...
+
+<!-- Please share a minimal reproducer which demonstrates the issue. `documentation/REPRODUCERS.md` gives some hints what an ideal reproducer should look like. -->
+
+<!-- Make sure you are able to reproduce the bug in the `main` branch, too. -->
+
+## Expected behavior
+
+<!-- A clear and concise description of what you expected to happen. Attach screenshots if needed. -->
+
+## Environment
+
+- Target device: [e.g. ESP32-S3] <!-- Use `espflash board-info` to get the target device iformation. -->
+- Crate name and version: [e.g. esp-hal 1.0.0]

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: true
+contact_links:
+  - name: Ask questions in Matrix channel (Recommended)
+    url: https://matrix.to/#/#esp-rs:matrix.org
+    about: Ask any questions directly in our Matrix channel.

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,24 @@
+---
+name: Feature request
+about: Suggest an idea for this project
+title: ''
+labels: ["feature request", "bug jury"]
+assignees: ''
+
+---
+
+## Motivations
+
+<!-- If your feature request is related to a problem, please describe it. -->
+
+## Solution
+
+<!-- Describe the solution you'd like. -->
+
+## Alternatives
+
+<!-- Describe any alternative solutions or features you've considered. -->
+
+## Additional context
+
+<!-- Add any other context or screenshots about the feature request here. -->

book/src/01_intro.md

@@ -4,6 +4,9 @@
 
 ## Content of this material
 
+> [!WARNING]
+> This training is currently out of date. We are working on a re-write in the [`feat/overhaul`](https://github.com/esp-rs/no_std-training/tree/feat/overhaul) branch.
+
 The goal of this book is to provide a getting-started guide on using the Rust programming language with Espressif SoCs and modules using `no_std` (bare metal) approach. To better understand this approach, see [Developing on Bare Metal (no_std)] chapter of [The Rust on ESP Book].
 
 The introductory trail will introduce you to the basics of embedded development and how to make the embedded board interact with the outside world by reacting to a button press, and lighting an LED.