Duplicate-path warnings missing from JSON validate output

[raifdmueller]

Description

dacli --verbose --format json validate outputs duplicate-path warnings only to stderr, but they are not included in the JSON output. Since dacli is designed for LLM integration (where consumers typically read only stdout/JSON), these warnings are invisible to automated consumers.

Reproduction

# Warnings visible on stderr:
dacli --verbose --format json validate 2>&1 | grep -i duplicate
# WARNING: Index: Duplicate section path: 'DACLI_TEST_RESULTS_v0.4' (first at .../v0.4.28.md:1, duplicate at .../v0.4.27.md:1)

# But NOT included in JSON output:
dacli --verbose --format json validate 2>/dev/null | python3 -c "
import json,sys
data = json.load(sys.stdin)
print('Warnings in JSON:', len(data['warnings']))
for w in data['warnings']:
    print(f\"  {w['type']}: {w['message']}\")
"
# Output:
# Warnings in JSON: 2
#   unclosed_block: Code block starting at line 6 is not properly closed
#   unclosed_table: Table starting at line 16 is not properly closed
# (no duplicate_path warnings)

Expected Behavior

Duplicate-path warnings should be included in the JSON warnings array, e.g.:

{
  "type": "duplicate_path",
  "path": "DACLI_TEST_RESULTS_v0.4",
  "message": "Duplicate section path (first at .../v0.4.28.md:1, duplicate at .../v0.4.27.md:1)"
}

Impact

LLM integrations that consume only the JSON output will not be aware of duplicate path issues in their documentation.

Related

• Related to Duplicate paths for files with dots in filename (e.g. version numbers) #266 (duplicate paths for files with dots in filename)

Environment

• dacli version: 0.4.26
• OS: Linux (WSL2)