Docs: Add headings so copy as markdown button shows up

docs/english/concepts/acknowledge.md

@@ -11,6 +11,9 @@ We recommend calling `ack()` right away before initiating any time-consuming pro
 :::
 
 Refer to [the module document](https://docs.slack.dev/tools/bolt-python/reference/kwargs_injection/args.html) to learn the available listener arguments.
+
+## Example
+
 ```python
 # Example of responding to an external_select options request
 @app.options("menu_selection")

docs/english/concepts/adapters.md

@@ -8,6 +8,8 @@ To use an adapter, you'll create an app with the framework of your choosing and
 
 The full list adapters, as well as configuration and sample usage, can be found within the repository's [`examples`](https://github.com/slackapi/bolt-python/tree/main/examples)
 
+## Example
+
 ```python
 from slack_bolt import App
 app = App(

docs/english/concepts/app-home.md

@@ -5,6 +5,9 @@
 You can subscribe to the [`app_home_opened`](/reference/events/app_home_opened) event to listen for when users open your App Home.
 
 Refer to [the module document](https://docs.slack.dev/tools/bolt-python/reference/kwargs_injection/args.html) to learn the available listener arguments.
+
+## Example
+
 ```python
 @app.event("app_home_opened")
 def update_home_tab(client, event, logger):

docs/english/concepts/authorization.md

@@ -12,6 +12,8 @@ For a more custom solution, you can set the `authorize` parameter to a function
 - **`enterprise_id`** and **`team_id`**, which can be found in requests sent to your app.
 - **`user_id`** only when using `user_token`.
 
+## Example
+
 ```python
 import os
 from slack_bolt import App

docs/english/concepts/commands.md

@@ -9,6 +9,9 @@ There are two ways to respond to slash commands. The first way is to use `say()`
 When setting up commands within your app configuration, you'll append `/slack/events` to your request URL.
 
 Refer to [the module document](https://docs.slack.dev/tools/bolt-python/reference/kwargs_injection/args.html) to learn the available listener arguments.
+
+## Example
+
 ```python
 # The echo command simply echoes on command
 @app.command("/echo")

docs/english/concepts/context.md

@@ -4,6 +4,8 @@ All listeners have access to a `context` dictionary, which can be used to enrich
 
 `context` is just a dictionary, so you can directly modify it.
 
+## Example
+
 ```python
 # Listener middleware to fetch tasks from external system using user ID
 def fetch_tasks(context, event, next):

docs/english/concepts/custom-adapters.md

@@ -18,6 +18,8 @@ Your adapter will return [an instance of `BoltResponse`](https://github.com/slac
 
 For more in-depth examples of custom adapters, look at the implementations of the [built-in adapters](https://github.com/slackapi/bolt-python/tree/main/slack_bolt/adapter).
 
+## Example
+
 ```python
 # Necessary imports for Flask
 from flask import Request, Response, make_response

docs/english/concepts/errors.md

@@ -4,6 +4,8 @@ If an error occurs in a listener, you can handle it directly using a try/except
 
 By default, the global error handler will log all non-handled exceptions to the console. To handle global errors yourself, you can attach a global error handler to your app using the `app.error(fn)` function.
 
+## Example
+
 ```python
 @app.error
 def custom_error_handler(error, body, logger):

docs/english/concepts/global-middleware.md

@@ -5,6 +5,9 @@ Global middleware is run for all incoming requests, before any listener middlewa
 Both global and listener middleware must call `next()` to pass control of the execution chain to the next middleware. 
 
 Refer to [the module document](https://docs.slack.dev/tools/bolt-python/reference/kwargs_injection/args.html) to learn the available listener arguments.
+
+## Example
+
 ```python
 @app.use
 def auth_acme(client, context, logger, payload, next):

docs/english/concepts/listener-middleware.md

@@ -6,6 +6,8 @@ If your listener middleware is a quite simple one, you can use a listener matche
 
 Refer to [the module document](https://docs.slack.dev/tools/bolt-python/reference/kwargs_injection/args.html) to learn the available listener arguments.
 
+## Example
+
 ```python
 # Listener middleware which filters out messages from a bot
 def no_bot_messages(message, next):

docs/english/concepts/logging.md

@@ -4,6 +4,8 @@ By default, Bolt will log information from your app to the output destination. A
 
 Outside of a global context, you can also log a single message corresponding to a specific level. Because Bolt uses Python’s [standard logging module](https://docs.python.org/3/library/logging.html), you can use any its features.
 
+## Example
+
 ```python
 import logging
 

docs/english/concepts/opening-modals.md

@@ -8,6 +8,8 @@ Read more about modal composition in the [API documentation](/surfaces/modals#co
 
 Refer to [the module document](https://docs.slack.dev/tools/bolt-python/reference/kwargs_injection/args.html) to learn the available listener arguments.
 
+## Example
+
 ```python
 # Listen for a shortcut invocation
 @app.shortcut("open_modal")

docs/english/concepts/select-menu-options.md

@@ -10,6 +10,9 @@ To respond to options requests, you'll need to call `ack()` with a valid `option
 Additionally, you may want to apply filtering logic to the returned options based on user input. This can be accomplished by using the `payload` argument to your options listener and checking for the contents of the `value` property within it. Based on the `value` you can return different options. All listeners and middleware handlers in Bolt for Python have access to [many useful arguments](https://docs.slack.dev/tools/bolt-python/reference/kwargs_injection/args.html) - be sure to check them out!
 
 Refer to [the module document](https://docs.slack.dev/tools/bolt-python/reference/kwargs_injection/args.html) to learn the available listener arguments.
+
+## Example
+
 ```python
 # Example of responding to an external_select options request
 @app.options("external_action")

docs/english/concepts/web-api.md

@@ -8,6 +8,8 @@ The token used to initialize Bolt can be found in the `context` object, which is
 
 :::
 
+## Example
+
 ```python
 @app.message("wake me up")
 def say_hello(client, message):