Lands the B6 increment (d8e5e811) on trunk. The fix itself is unchanged from that commit and its full reasoning is recorded there; this message covers the landing, because the merge was not a formality.

WHAT B6 FIXES

`tag` was read-only. `tag list` was the only subcommand, so a repository could not be given a name for a check-in at all. Unlike the other five blockers this was not a wrong answer — the verb told the truth about what existed — but the capability was simply absent. `zit tag add NAME CHECKIN` now mints one CONTROL artifact carrying a single `T +sym-NAME` card, targeting the resolved check-in's 64-hex hash.

THE SIGN IS THE WHOLE CORRECTNESS ARGUMENT

The card is a SINGLETON (`+`), not a propagating (`*`) tag. `resolveName` (src/repostate.zig:891) picks the max-`event.mtime` check-in among ALL active `sym-` rows, so a propagating `*sym-v1` would be inherited by every descendant and then resolve to the NEWEST of them — the name would silently drift off the check-in the user tagged, which is the same class of wrong answer as B1. `applyTagOps` (src/repostate.zig:727) gates propagation on `op.type != .singleton`, so a `+` card pins the name with ZERO repostate changes. The contrast with a branch is deliberate: a *branch* sym propagates precisely because descendants must inherit it; a *tag* sym does not, precisely because they must not.

CONFLICT RESOLUTION, STATED

One conflict, src/e2e.zig, positional rather than semantic: trunk's B5 block and B6's block are both appended at the end of the file over an empty common ancestor. Fossil again emitted the five-part conflict rather than the usual four — a "####### SUGGESTED CONFLICT RESOLUTION follows" section carrying its own proposed merge sits between the local copy and the ancestor section. Splitting only on the four familiar markers swallows that separator into the kept text, which then compiles as garbage; B3's landing recorded the same trap and it recurred here verbatim.

The two candidate sections were compared before choosing: the SUGGESTED section and the MERGED IN section are byte-identical (257 lines each), and the common ancestor is a single empty line. The resolution keeps trunk's 8 B5 tests plus exactly one copy of B6's 5-test block. Verified post-resolution: no residual marker of any of the five kinds, 432 tests in the file, no duplicated test name, and the B3 (5), B5 (8) and B6 (7) blocks all present at their expected counts. One further edit was needed — the splice left a doubled blank line at the seam, which `zig fmt` flagged; the reformat is that one blank line and nothing else.

TEST EVIDENCE ON THE MERGED TREE

Re-verified on trunk after the merge, not inherited from the branch: `zig fmt --check .`, `zig build`, `zig build test`, `zig build e2e` (432/432, no filtering), `zig build dst` (6 seeds x 1000 steps) and `zig build smoke` (S1-S6) each exit 0. `fossil extras --dotfiles` is empty.

The blocker repro was also driven by hand against the rebuilt merged binary rather than inferred from the source: `zit tag add v1 tip` exits 0 and prints the artifact hash; after a second commit `zit cat a.txt v1` is the tagged content while `zit cat a.txt tip` is the newer one, and `zit tag list tip` does NOT carry v1 — the singleton pins and is not inherited. `zit tag add v1` alone is a usage error at exit 2, and `zit tag add v2 nosuchcheckin` exits 1 naming the check-in and leaves no tag behind.

CHANGED EXPECTATIONS (all three encoded the missing capability, nothing else)

cli tag B-tag-7 (src/cli.zig) and cli tag B-tag-13 (src/e2e.zig) used the literal token `add` as their stand-in for "not a subcommand". `add` IS one now, so both use `cancel`, a word that still is not — cancel/remove semantics stay deferred to 0.2. cli tag B-tag-11's verbatim `tag_help_expected` gains the `add` usage line and its paragraph, because `tag --help` must teach the new grammar. The diff was audited for other expectation changes and there are none.

RECORDED, NOT ASSUMED: branch creation shares no read-only gap. It is already served by `commit --branch`, which mints the propagating branch/sym pair directly on the check-in manifest (src/cli.zig `composeCommitTags`), so there is no `branch add` to write.

No borrowed technique: the singleton-sign argument and the `mintControlArtifact` extraction are original to this change. No performance claim is made. check-in: a5b6db7a8c user: dmestas tags: trunk