fix: use correct Bitbucket API for user workspaces and clarify repo config

The `/workspaces` API endpoint was updated to `/user/workspaces` to correctly retrieve workspaces for the authenticated user.

Configuration guidance for `DEFAULT_WORKSPACE` and `DEFAULT_REPO` in documentation and templates now explicitly references deriving these values from the Bitbucket repository URL, simplifying initial setup.

README.md

@@ -95,6 +95,8 @@ Add the MCP server to your Claude configuration:
 > **Important:**
 > - Replace `/absolute/path/to/bitbucket-mcp` with the actual absolute path where you cloned the repo.
 > - `DEFAULT_WORKSPACE` and `DEFAULT_REPO` are optional but convenient — they let you omit those parameters from every tool call.
+> - Read them directly from your Bitbucket repo URL: `https://bitbucket.org/{workspace}/{repository}/pull-requests`
+>   For example, `https://bitbucket.org/my-workspace/my-repo/pull-requests` → `DEFAULT_WORKSPACE=my-workspace`, `DEFAULT_REPO=my-repo`
 > - Get your API token from [Atlassian API Tokens](https://id.atlassian.com/manage-profile/security/api-tokens).
 
 ### 4. Verify