* fix: write the ticket event row with its tag (#184), quiet the cascade (#186)

crosslinkTicket applied the tkt-<uuid> tag and returned the event row as a pending item for a second pass that was a no-op stub, so the row was never written at all. collectCrosslinkCandidates excludes any blob that already has a tagxref row naming its own rid as srcid, so the tag the incomplete operation wrote also hid the artifact from every later sweep. Cloning fossil's own repository produced 96 event rows of type 't' against canonical fossil's 3,808 -- 100% of the D,J,K,U,Z ticket-change shape lost, with nothing logged and test-integrity still clean, because only derived tables were wrong.

Implement the ticket rebuild instead of reordering the writes: there was no event write to reorder. ticketRebuildEntry replays every artifact carrying the ticket's tag in mtime order and derives its ticket, ticketchng and event rows, mirroring fossil's ticket_rebuild_entry, ticket_insert and manifest_ticket_event. It runs inline in the transaction that writes the tag, so the marker meaning "already linked" and the rows that make that true commit together or not at all. Replaying the whole tag set per artifact also makes the result independent of arrival order.

The event wording, the ticket/ticketchng column mapping including '+field' append semantics, the %h escaping and the two hyperlink hash lengths were all derived from the fossil binary rather than assumed, and are pinned by TestFossilBinaryTicketParity: a corpus built with `fossil ticket add`/`change` is crosslinked by us, rebuilt by fossil, and the two derivations compared row for row. TestCrosslink_TicketArtifactsProduceEventRows is the count assertion whose absence let this ship.

Audited the other three exclusion predicates for the same split-write shape: forumpost and attachment are each written by the same function, in the same transaction, as the event row that accompanies them, and propagate errors, so neither can diverge. No change made to them.

Secondary (#186): AfterDephantomize warned once per blob that failed to parse as a manifest, which is the ordinary outcome for file content and what the whole-repository sweep has always skipped silently -- ~39k lines on a fossil clone, burying the failures that matter. It now skips them the way linkBatch does. A blob that parses but fails to link is still a real fault and still warns.

* docs: record the ticket rebuild's measured cost and why it stays inline

The inline rebuild is quadratic in one ticket's artifact count. The cheaper deferred shape stays atomic but needs two call sites to remember to invoke it, and a forgotten call reintroduces #184 silently. Write the measurements and that reasoning down at the function, so a later profile of a repository with one hot ticket does not turn into an optimization back into the bug. check-in: 39f646e0ae user: [email protected] tags: trunk