feat: add local-cluster MoE, dense sharding, and WebGPU workers

[gauravsaini]

Summary

This PR adds a progressive local-cluster execution path for consumer Macs and browser/WebGPU devices:

• coordinator/worker registration and distributed MoE expert routing
• native batch-union expert RPC for disk-backed workers
• contiguous dense MLP activation sharding across local nodes
• browser/mobile WebGPU expert workers over WebSocket
• native TCP-to-WebSocket activation proxy
• WebGPU expert weight exporter for readable floating-point checkpoints
• browser worker UI and protocol/dispatch tests

The coordinator keeps token generation, routing, attention, and KV state local. Remote workers execute assigned expert FFNs or dense MLP ranges.

Validation

• native make test
• 73 Python tests
• 17 web tests
• TypeScript/Vite production build
• Python and JavaScript syntax checks

Scope and follow-ups

The WebGPU path currently uses f32 buffers and is intended for a trusted LAN. TLS/authentication, WebRTC transport, quantized WebGPU weight formats, and broader dense/tensor-parallel sharding can follow as separate changes.

Not yet tested (sorry for being gpu poor) :

Real C coordinator → dense worker COLIDN01 end-to-end
Dense shard output equivalence against local computation
Real C → WebGPU browser integration
WebGPU FFN numerical correctness against a CPU reference
Exporter tests
Actual iPhone/Android/WebGPU hardware smoke test

[gauravsaini]

@JustVugg: Alla vostra attenzione 😀

[JustVugg]

Heads-up: c/glm.c was just split into c/colibri.c + header modules (#391, now merged into dev). This PR touches the old glm.c, so it will need a rebase onto current dev with its changes moved into colibri.c (or the relevant extracted header: quant.h, sample.h, kv_persist.h, telemetry.h, grammar.h). The make glm target still works (alias of make colibri), so no build scripts break. Apologies for the churn — ping me if the rebase gets thorny and I can help place the hunks.

[JustVugg]

Rebase needed: this has been in conflict against dev for a while and today's merges (#298, #192) widened it. It bundles three big features (local-cluster MoE, dense sharding, WebGPU workers) — honestly it would land much more easily as three separate PRs, each rebased on current dev. Would you be up for splitting it? The cluster piece especially has overlap with the direction in #431/#432 worth reconciling.