feat(cli): remove mem0 version subcommand from md files and fix help --json in the Python CLI (#6773)

cli/python/README.md

@@ -241,14 +241,6 @@ Verify your API connection and display the current project.
 mem0 status
 ```
 
-### `mem0 version`
-
-Print the CLI version.
-
-```bash
-mem0 version
-```
-
 ## Agent mode
 
 Pass `--agent` (or its alias `--json`) as a **global flag** on any command to get output designed for AI agent tool loops:
@@ -307,6 +299,8 @@ These flags are available on all commands:
 | `--base-url` | Override the configured API base URL for this request |
 | `-o, --output` | Set the output format |
 
+`mem0 --version` prints the CLI version. It is only valid before a subcommand, not after one.
+
 ## Environment variables
 
 | Variable | Description |