Do not use CWD as a fallback for --project-from-cwd

This can be problematic if CWD is, for example, the user's home directory.
Fixes #979

docs/02-usage/020_running.md

@@ -162,8 +162,8 @@ to get a list of all available options.
 Some useful options include:
 
   * `--project <path|name>`: specify the project to work on by name or path.
-  * `--project-from-cwd`: auto-detect the project from current working directory   
-    (looking for a directory containing `.serena/project.yml` or `.git` in parent directories, activating the current directory if none is found);  
+  * `--project-from-cwd`: auto-detect the project from current working directory     
+    (looking for a directory containing `.serena/project.yml` or `.git` in parent directories and activating the containing directory as the project root, if any).
     This option is intended for CLI-based agents like Claude Code, Gemini and Codex, which are typically started from within the project directory
     and which do not change directories during their operation.
   * `--language-backend JetBrains`: use the Serena JetBrains Plugin as the language backend (overriding the default backend configured in the central configuration)

docs/02-usage/030_clients.md

@@ -96,7 +96,7 @@ claude mcp add --scope user serena -- uvx --from git+https://github.com/oraios/s
 ```
 
 Whenever you start Claude Code, Serena will search up from the current directory for `.serena/project.yml` or `.git` markers,
-activating the current directory as the project if neither is found. 
+activating the containing directory as the project (if any). 
 This mechanism makes it suitable for a single global MCP configuration.
 
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