Adding diverse topic coverage:
- blog-008: buying_guide — OEM vs compatible real cost numbers
- blog-009: migration_guide — 100G→400G what actually breaks
- blog-010: technology_deep_dive — QSFP-DD vs OSFP form factor reality
- blog-011: tutorial — transceiver procurement checklist
All follow FO rules: no markdown headers in body, no bullet lists,
one thesis, engineer voice, ~1000 words. Total training set: 11 articles.
