arcint 1.6.0 — prompt experts on int8 DPAS, the head file, card sampling

This is not the current release. The current one is here, with its changes in CHANGELOG.md.

Prompt expert products on int8 DPAS on the Arc A770, a head file without output.weight, two more models admitted, sampling defaults from the model card. The full record is in CHANGELOG.md. This is the first GitHub release since 1.2.6; the changelog covers the versions between.

• Prefill +13.8 % at 41k on the A770 for the Qwen3.6 coder model (patches 0102-0104): the prompt's expert products run on int8 DPAS with no local memory, and a sub-group owns two sets of weight rows on one activation read. 845 -> 962 t/s; at 4,096 tokens 1,915 -> 2,150 t/s. The B60 does not change.
• An MTP head file may carry no output.weight (patch 0105, tools/coder_mtp_gguf.py). That coder model's draft head had been pruned along with its trunk, and the base model's unpruned head on the pruned trunk gives +3.3 % under deployed sampling and +2.2 % at a 93.7k prompt, with no training. The head file is not shipped, and the method is in the repository.
• Gemma 4 E4B and Granite 4.2 8B are admitted by architecture and geometry. They are not yet served by a unit and have no card numbers.
• Sampling defaults come from the model card in the GGUF; /props reports provenance card. A unit that passes no sampling flags moves to its card's row: the shipped Flash-Next and TTS units pin the row they have served at. --llama-checkpoints N above 0 is now refused on a model with no recurrent memory.
• docs/concepts.md: what arcint implements for Intel Arc inference, what it gained on which card, where the code is, and what was tried and not adopted. The branch flattened holds the pinned llama.cpp with the released patch series applied, so the code reads as files.

Release gate against 1.5.4, same window (measured-here): Flash-Next and the agent pass. The coder fails one decode cell, accepted by the operator: decode a +5.6 %, b -6 %, c equal, with different texts and a verify's cost level; 12 answers 82.66 -> 81.95 t/s; the acceptance task 10/10 x3. KL against the file's CPU reference .00585 -> .00803, inside the bar. 0105 was measured in its own windows, not in that gate.

The attached .deb is built from this tag's tarball for Debian 13 (trixie) on x86_64 and needs Intel's compute runtime.