[Doc] Drop the trailing slash from directory paths in the documentation

Directory paths in prose were written inconsistently: `examples/` next to `examples/rails` in
the README and on the Examples page, `app/tools/` next to `config/routes.rb`, and `rails/` in
an examples README heading. The trailing slash carries no information in prose, so every directory path in
user-facing markdown now follows the no-trailing-slash form.

Author: koic

README.md

@@ -125,7 +125,7 @@ see [Client Transports](https://ruby.sdk.modelcontextprotocol.io/client/transpor
 
 ## Examples
 
-Runnable examples are available in [`examples/`](https://github.com/modelcontextprotocol/ruby-sdk/tree/main/examples),
+Runnable examples are available in [`examples`](https://github.com/modelcontextprotocol/ruby-sdk/tree/main/examples),
 including a complete Rails application in [`examples/rails`](https://github.com/modelcontextprotocol/ruby-sdk/tree/main/examples/rails).
 
 ## Documentation

docs/examples.md

@@ -7,7 +7,7 @@ permalink: /examples/
 
 # Examples
 
-Runnable examples live in [`examples/`](https://github.com/modelcontextprotocol/ruby-sdk/tree/main/examples) in the repository.
+Runnable examples live in [`examples`](https://github.com/modelcontextprotocol/ruby-sdk/tree/main/examples) in the repository.
 
 ## Standalone Scripts
 
@@ -30,7 +30,7 @@ See [`examples/README.md`](https://github.com/modelcontextprotocol/ruby-sdk/blob
 
 [`examples/rails`](https://github.com/modelcontextprotocol/ruby-sdk/tree/main/examples/rails) is a complete, minimal
 Rails application serving an MCP server over the Streamable HTTP transport. The server and transport are built once
-at boot and mounted at `/mcp` in `config/routes.rb`; tools live in `app/tools/`, and a text resource is served through
+at boot and mounted at `/mcp` in `config/routes.rb`; tools live in `app/tools`, and a text resource is served through
 a `resources_read_handler`.
 
 ```console

examples/README.md

@@ -141,10 +141,10 @@ The client will:
 - Provide an interactive menu to trigger notifications
 - Display all received SSE events in real-time
 
-### 7. Rails Server (`rails/`)
+### 7. Rails Server (`rails`)
 
 A minimal Rails application that mounts `StreamableHTTPTransport` in its routes, following the "Rails (mount)" pattern from the top-level README.
-It demonstrates class-based tools in `app/tools/` and a resource with a read handler.
+It demonstrates class-based tools in `app/tools` and a resource with a read handler.
 
 **Usage:**