fix(test): remove retry masking and output filtering in database integration test

- Remove silent retry logic in Run Python Script that masked intermittent
  failures by retrying on empty stdout + non-zero RC
- Change output filter from 'in' to 'startswith' so only lines beginning
  with log prefixes are filtered, not lines containing them mid-string
- Remove [error from the filter list so error lines are never silently
  discarded from test output

Fixes #898

robot/database_integration.robot

@@ -760,16 +760,6 @@ Run Python Script
     ${temp_file}=    Evaluate    (lambda t: (__import__('os').close(t[0]), t[1])[-1])(__import__('tempfile').mkstemp(suffix='.py', dir='/tmp'))
     Create File    ${temp_file}    ${full_code}
     ${result}=    Run Process    ${PYTHON}    ${temp_file}    timeout=60s    stderr=STDOUT    env:PYTHONWARNINGS=ignore    env:PYTHONDONTWRITEBYTECODE=1
-    # Retry once when the process was likely killed by a signal (OOM / CPU
-    # starvation under heavy parallel CI load).  A signal-killed process
-    # produces empty stdout because its output buffer is never flushed.
-    IF    ${result.rc} != 0
-        ${stdout_len}=    Get Length    ${result.stdout}
-        IF    ${stdout_len} == 0
-            Sleep    3s    reason=Retrying after transient subprocess failure (rc=${result.rc})
-            ${result}=    Run Process    ${PYTHON}    ${temp_file}    timeout=60s    stderr=STDOUT    env:PYTHONWARNINGS=ignore    env:PYTHONDONTWRITEBYTECODE=1
-        END
-    END
     Remove File    ${temp_file}
     # Check if process failed and log stderr if present
     IF    ${result.rc} != 0
@@ -782,7 +772,7 @@ Run Python Script
     FOR    ${line}    IN    @{lines}
         ${stripped}=    Strip String    ${line}
         # Skip debug/logging lines
-        IF    '${stripped}' != '' and not '[debug' in '${stripped}' and not '[info' in '${stripped}' and not '[warning' in '${stripped}' and not '[error' in '${stripped}'
+        IF    '${stripped}' != '' and not '${stripped}'.startswith('[debug') and not '${stripped}'.startswith('[info') and not '${stripped}'.startswith('[warning')
             Append To List    ${filtered_lines}    ${stripped}
         END
     END