docs: describe the memory model as built, and fold the loose files into Antora

[michalharakal]

Closes the documentation half of #932: the storage model, the packed-weight contract and the planning tools existed only in design records under docs/design/ and in issue threads. Antora is the docs site, so they belong in it — and the loose Markdown files are gone.

New pages

• explanation/memory-model.adoc — the model as built: Storage owns bytes, Format says what they mean, Layout says where they are, Scope says how long they live, and TensorView is what a kernel receives. Mermaid class diagram, the decode-step dispatch flow, the two-pool device check, what the observability stream carries, and the numbers measured on an ARMv8.2 Cortex-A55 board. Known limits are stated rather than implied — packed weights still reach the managed heap, mapping is whole-file only.
• explanation/packed-weight-layout.adoc — the normative block-order contract, promoted from a design record. The two orders, where the order lives, how to convert, the load-boundary orientation rule, what a downstream repository consumes, and the five rules. Kdocs and error messages now point here.
• how-to/plan-model-memory.adoc — skainet plan, the device profiles, the two-pool fit check, mapped staging on Android, and plan-vs-actual, with real output rather than descriptions of output.
• explanation/eager-execution.adoc — the backends-and-kernels map that was a loose Markdown file, now a page with the kernel × provider and platform tables and the current gaps.

arc42 refreshed

reference/architecture.adoc describes what is there now:

• §5.3 Memory model — new building block with a mermaid class diagram showing how Tensor / TensorData sit above TensorView / Storage / Format / Layout / Scope.
• §6 Runtime view — the ASCII pipeline redrawn as two mermaid flows: the op-level path, and the view/dispatch path (normalize rank → build KernelKey → look up → insert a visible adapter → reference kernel).
• §8 Cross-cutting — scoped memory, conversions as events, the block-order contract, one observability stream.
• §9 Decisions — five rows for the storage-first model, key-based dispatch, block order in the layout, matmulWeightTransposed, and quantPolicy × staging.
• §10 / §11 / §12 — memory quality criteria (flat memory, plan-vs-actual, the golden gate), current risks in place of stale ones, and glossary entries for the new vocabulary.

Diagrams are mermaid throughout, per the repo's offline-mermaid Antora image.

Loose files: folded in, then deleted

Deleted	Where its content went
docs/design/memory/memory-architecture-proposal.md, …-milestones-prd.md	the memory model page; SKEEP-003 now xrefs the as-built pages
docs/design/memory/packed-weight-layout.md	explanation/packed-weight-layout.adoc
docs/design/memory/m2-acceptance.md, spike-…, baseline-…	the "Measured" section of the memory model page
docs/eager-execution-backends-and-kernels.md	explanation/eager-execution.adoc
docs/export/minerva.md	its bundle-layout and graph-source sections moved into how-to/minerva-export.adoc

docs/.docker/README.md stays — it documents the Docker image sitting next to it, not the product.

References in kdocs, error messages, README.md, SKEEP-003 and the kernel matrix now point at the pages. CHANGELOG.md keeps its historical mention, since it records what was true at that release.

Gate

scripts/pr-gate.sh — all legs passed (the .kt files touched are kdoc and error-message text).

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The documentation has been built successfully for this PR.

Generated Files:

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• JSON schema output: operators.json

Artifacts:

• Download the documentation-preview-1106 artifact to view the complete documentation locally.

This comment will be updated automatically when the PR is updated.