Changes touching this path

• loot archive grows prefix, format, -o and a pathspec, and the pathspec is the DECLARED group rather than a fourth matcher: no Glob, no matches and no string compare against a pattern is written anywhere in this change, so the empty-match refusal and the 1330 cwd rebase arrive free with the attachment. the attachment forced one thing the ticket did not name - archive was declared NO_PATHS, so under 1551 the group trailing list would have begun at position ZERO and swallowed the output file - and it now states its own arity of two opaque slots first, both opaque because a file name, an -o value and a prefix are not repo paths and must not be rebased. the honesty criterion is the one that carried risk, since this adds a SECOND reason an archive can be partial beside the reason 416 built the summary for, and the two must not collapse into one number that reads as either: three populations are kept apart, written, then unreadable as selected minus written which KEEPS 416 word partial, then outside as total minus selected which gets its own clause, its own denominator and the explicit words by request not unreadable. the first denominator switches to selected and SAYS selected exactly when a pathspec is in force, so 1 of 2 cannot be read against a five path change, and the pathspec clause prints EVEN AT ZERO because silence there is indistinguishable from no pathspec at all. written is derived from selected by MEMBERSHIP, so written under selected under total holds by construction rather than by a subtraction that could underflow, and the engine skipped count is deliberately NOT used because it is taken over the whole tree and would therefore count paths the operator never asked about - that IS the collapse. the format is tar.zst and it adds an EDGE rather than a crate: zstd is already default-on in loot-codec and loot-core takes it with default features, so it already compiles into the shipped binary and the lock gained exactly one line with no new package. gzip was rejected on MEASUREMENT rather than taste - flate2 is in the lock but its only dependent is automerge, which only spike-crdt links, so it reaches NO shipped binary and choosing it would put a second compressor in the released loot; the wider extractor reach is the real cost and the format table says so. it does not reuse the codec own compressor either, because sharing it would weld archive bytes, a thing people compare hashes of, to a level chosen for objects in a store. the byte-reproducibility promise is NARROWED where an operator reads it: the ustar bytes are host independent, the zstd framing is reproducible only for a given zstd build. two pins were aimed rather than merely live - the -o ambiguity mutation is invoked with @ rather than HEAD precisely so the mutated build SUCCEEDS, which makes refusal the assertion, and tar.zst is checked by DECOMPRESSING rather than by length, since a wrap that compressed the wrong buffer stays green under a size assertion. and a stale doc claim was found on the way: readable_tree was described as what loot grep searches, false since 1500 moved grep to readable_object, narrowed here and in the copy of it that archive carried (#1530) 95a1cfeb · dbf3dbe6…

Renames are not followed. loot's tree maps a path to an address, so a rename is a delete and an add. This list is the history of the name, not of the bytes.