Add LLM key-hunter toolkit, vault, and skill

- tools/scripts/llm-key-hunter: GitHub leak hunting pipeline (hunt_*,
  pivot miner, two-layer verify/content caches, per-provider verification)
- usable_keys: verified key vault across 12 providers (deepseek, minimax,
  volcanoark, longcat, codingplan, zhipu free-tier, mimo, siliconflow, etc.)
- .grok/skills/llm-key-hunter: operator skill for the hunt/verify/vault flow
- NewAPI channel import scripts and CDP capture helpers
- Result verdict buckets (excluding multi-GB blob caches and dedup dumps)

tools/scripts/llm-key-hunter/usable_keys/mimo/PLAN_SUMMARY.txt

@@ -0,0 +1,8 @@
+Xiaomi MiMo (小米 MiMo) — Token Plan
+===================================
+Key prefix: sk-cx- (51 chars)
+OpenAI:    https://api.xiaomimimo.com/v1
+Anthropic: https://api.xiaomimimo.com/anthropic
+Model: mimo-v2.5
+Usable keys: 1
+Found via .claudian/claudian-settings.json (claude-code routing to MiMo).