docs(skills): update curation workflow

[gildesmarais]

What changed

• Refactored html2rss-config skill into a router: mode deltas live in reference/, quality gate stays in AGENTS.md
• Added curation-verbs.md documenting bare CLI/MCP verbs (inspect, recon, capture, test, apply, scrape) and stale-catalog recovery
• Added scripts/add_config (automated create via recon/capture) and scripts/html2rss_api.rb (gem facades)
• Updated check_config to run validate + test (not feed); register_botasaurus and paths stay on lib/html2rss/configs/
• Slimmed batch_recon and probe_rss to delegate to core CLI; simplified batch.md, new.md, pitfalls.md
• AGENTS.md / README.md: document apply as primary verb (feed is alias)

Why

The html2rss gem renamed CLI/MCP verbs (dropped _url/_config suffixes). Skill docs and scripts still referenced old names and duplicated the quality gate. This aligns the configs-repo agent workflow with the frozen verb contract and reduces drift surface.

Risk

• Docs/scripts only — no feed YAML changes
• add_config is new automation; manual fallback path unchanged
• Low rollout risk; agents may need MCP reload if catalog still shows old tool names (documented in curation-verbs.md)

Review map

1. .agents/skills/html2rss-config/reference/curation-verbs.md — verb table, journeys, MCP catalog-mismatch fix
2. .agents/skills/html2rss-config/scripts/add_config — automated create path and topic validation
3. .agents/skills/html2rss-config/scripts/check_config — test golden path + fetch spec resolution
4. AGENTS.md — MCP section and quality-gate wording

Validation

• Conflict resolution during rebase onto master (flat-refactor commits dropped intentionally)
• Not run: make validate, make test