feat(atlas): section TD, structured EIP-712, with hardware evidence

[BitHighlander]

Four entries for the structured EIP-712 walk, and the first section in this catalog whose expected values come from outside this repository.

TD1 asserts the domainSeparator and messageHash published by assets/eip-712/Example.js in ethereum/EIPs — the reference implementation the spec links to — republished by Example.sol, by eth-sig-util's V3 and V4 snapshots, and by Mrtenz/eip-712.

That distinction is the section's reason to exist. The firmware C, the hdwallet TypeScript and the python client were written by one hand against one reading of the spec, so three of them agreeing proves the reading is self-consistent and nothing more. A shared misreading produces three consistent wrong answers. It cannot produce those two numbers.

Hardware evidence, recorded in the notes

2026-08-21, K1-14AM, unsigned build of the 7.15 line:

• nine screens, one per leaf, all correct on operator review
• 42-character addresses rendered in full — the truncation class that shipped as a bug at >42 chars, and the one claim the emulator's framebuffer genuinely cannot settle
• the published hashes matched on silicon, not just in the emulator
• device address 0x73d0385F4d8E00C5e6504C6030F47BF6212736A8, identical to the emulator, so key derivation agrees too

TD2 covers arrays, refused outright until a kilobyte came back from MAX_DECODE_SIZE (at 13 KB the ARM image missed the linker's runtime-reserve gate by 204 bytes; at 12 KB it clears by 812). TD3 covers a fixed dimension checked against the document — the count is the only thing the device is ever told. TD4 covers the AdvancedMode gate.

Section id is two characters because all 26 letters were taken; the catalog keys on a string.