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/results/medium/OpenAI/no_balance.txt

@@ -0,0 +1,3 @@
+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|https://github.com/TC960/KnightLabV2/blob/c00a30c3988d744d3e3e62132800100ec21388a2/proj_2_attempt3/archive/prev_methods/withLLMs/take2.ipynb|[retry] chat 429: {
+    "error": {
+        "message": "You have no credits remaining. Add credits to continue using the API at https://pla