style: fix ruff lint and formatting errors

- E741: rename ambiguous variable `l` → `line_text` in enhance_skill_local.py
- ARG001: suppress unused `doc` param in word_scraper _build_section()
- SIM108: use ternary for code_text assignment in word_scraper
- F841: remove unused `metadata` variable in test_chunking_integration
- F401: remove unused imports in test_pinecone_adaptor
- ARG001: rename unused `docs` → `_docs` in test_pinecone_adaptor
- Format 20 files to match ruff formatting rules

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/skill_seekers/cli/enhance_skill_local.py

@@ -367,7 +367,7 @@ class LocalSkillEnhancer:
             if line.startswith("#"):
                 # Found heading - keep it and next 3 lines
                 chunk = lines[i : min(i + 4, len(lines))]
-                chunk_chars = sum(len(l) for l in chunk)
+                chunk_chars = sum(len(line_text) for line_text in chunk)
                 if current_chars + chunk_chars > max_chars:
                     break
                 result.extend(chunk)