* feat(proxy): add LITELLM_OFFLINE_MODE to stop every request the proxy makes on its own
* fix(ui): name LITELLM_OFFLINE_MODE where the cost map panel says local mode is forced
* test: isolate the offline-mode tokenizer tests from the local Hugging Face cache
* test: cover the offline policy templates and the cached Kimi K3 tokenizer
* test(integration): count Kimi K3 tokens in the offline-mode egress test
* refactor(token_counter): skip non-bundled tokenizers in offline mode instead of listing downloaded ones
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Co-authored-by: yucheng-berri <293926326+yucheng-berri@users.noreply.github.com>
