Fix: MoE Memory Budgeting and Dynamic Multimodal Tokens - #98

Thanks @roydsouza — and credit where due: the multimodal BOA/EOA half of this landed via your #104 in May, and it has been on main with tests since (9d495d9, 621a931). The MoE-detection half is now superseded by #114, which extends the same idea to all three expert-key spellings (num_local_experts / num_experts / n_routed_experts, plus nested text_config).

What remains unique here is the MoE memory buffer and the swap-usage warning, and both are worth having. One fix needed on the swap monitor: the hand-declared xsw_usage struct has xsu_used / xsu_avail in the wrong order relative to Darwin's sys/sysctl.h (real layout is xsu_total; xsu_avail; xsu_used;), so the warning fires on available rather than used swap — using Darwin's imported xsw_usage directly avoids both the bug and the type shadowing.

This branch also carries an accidental working-tree state that reverts ~2,300 lines of unrelated shipped code (speculative-decoding dispatch, ModelDownloader, SettingsView, several safety gates), so rather than rebasing it, a fresh small PR on current main with just those ~40 lines — the computeSSDMemoryBudget MoE buffer and the corrected swap warning — would be the clean path. Happy to help set that up if useful.

Closing in favour of the pieces that already landed (#104, #114). The buffer + swap-warning invitation stands.