docs: Simplify verbose docstrings

- save_map_file(): 55 lines → 12 lines
- is_legacy_backend(): 42 lines → 11 lines
- _check_response_for_errors(): 40 lines → 9 lines

Keep essential info, remove redundant examples and explanations.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

haproxy_mcp/haproxy_client.py

@@ -91,43 +91,12 @@ def haproxy_cmd_checked(command: str) -> str:
 def _check_response_for_errors(response: str) -> None:
     """Check HAProxy response for error indicators and raise if found.
 
-    HAProxy Runtime API returns plain text responses. Success responses are
-    typically empty or contain requested data. Error responses contain
-    specific keywords that indicate the command failed.
-
     Args:
-        response: Response string from HAProxy Runtime API command.
+        response: Response string from HAProxy Runtime API.
 
     Raises:
-        HaproxyError: If response contains any error indicator keyword.
-
-    Error Indicators:
-        - "No such": Resource doesn't exist (e.g., backend, server, map entry)
-        - "not found": Similar to "No such", resource lookup failed
-        - "error": General error in command execution
-        - "failed": Operation could not be completed
-        - "invalid": Malformed command or invalid parameter value
-        - "unknown": Unrecognized command or parameter
-
-    Examples:
-        Successful responses (will NOT raise):
-            - "" (empty string for successful set commands)
-            - "1" (map entry ID after successful add)
-            - Server state data (for show commands)
-
-        Error responses (WILL raise HaproxyError):
-            - "No such server." - Server doesn't exist in specified backend
-            - "No such backend." - Backend name not found
-            - "No such map." - Map file not loaded or doesn't exist
-            - "Entry not found." - Map entry lookup failed
-            - "Invalid server state." - Bad state value for set server state
-            - "unknown keyword 'xyz'" - Unrecognized command parameter
-            - "failed to allocate memory" - Resource allocation failure
-            - "'set server' expects <addr>:<port>" - Invalid command syntax
-
-    Note:
-        The check is case-insensitive to catch variations like "Error:",
-        "ERROR:", "error:" etc. that HAProxy may return.
+        HaproxyError: If response contains error keywords
+            (No such, not found, error, failed, invalid, unknown).
     """
     error_indicators = ["No such", "not found", "error", "failed", "invalid", "unknown"]
     if response: