D200 - The file formats moved to selfish, and this repository now depends on them

Four modules and four data files left this tree. tool/src/ lost 2,801 lines:

gone	now
nid.rs (289)	selfish-nid
dynlib.rs (1,499)	selfish-elf::dynlib, both directions
module.rs (258)	selfish-elf::identity
mkself.rs (755)	selfish-container
data/hash-suffix.toml, self-format.tsv, pkg-format.tsv	selfish/data/
link/module.ld	selfish/link/module.ld

data/ now holds only this project's own measurement products - the mined corpus, the surface census, the GPU surface table. That is the split the sibling repository exists to make: a format is shared, a measurement stays with whatever measured it.

What did not move: the manifest. Which library resolves which name is this project's, and selfish::dynlib::build takes it as a closure. So is imports::PREENCODED, the $ sigil marking a symbol whose name is the identifier - a convention of this project's symbol tables rather than a fact about the format.

It was checked by this repository's own verifier

mkmodule re-derives the tag assignment from the bytes it just wrote, and that derivation knows nothing about how they were produced:

p.elf: EI_OSABI 0x0000 -> 0x0009
p.elf: e_type 0x0003 -> 0xfe10
p.elf: vendor segment at 0x297e0, 408 bytes, 23 tags, 1 symbols from 1 libraries
p.elf: layout reproduces the tag derivation (9 relations)

selftest still matches the published pair through the moved suffix, and 204 tests pass - ten fewer than before, which is the ten that went with the modules.