* feat: built-ins record their origin, and an item made from one can be offered Pad's current text (TASK-3462 U1+U2)
U1: every convention and playbook Pad ships has a stable key and a content
hash; template seeding and the new server-side POST /library/activate record
{key, seed hash, seed text} in item_builtin_origin (migration 128 / pg 102).
CLI, remote MCP and the web Library page activate through the endpoint;
seeded and activated copies of an entry store the same fields. Export/import
carry the origin; copies get none; a request body cannot claim one.
U2: GET /items/{ref}/builtin derives current / update_available / diverged /
unknown_origin / unknown_entry; POST /items/{ref}/builtin/update takes the
library text through the ordinary PATCH path (expected_seq required, status
and title untouched, a forced version row keeps a diverged item's edits);
GET /builtins lists states in one join, showing only fully visible
collections.
* fix: the origin's seed text is NUL-protected (trigger migration 129); the MCP activate test asserts the endpoint call; activation follows the declared kind server-side (TASK-3462)
* fix: the built-in seed moves in the update's own transaction; a NUL-bearing imported origin is skipped; the listing computes visibility once; numbers hash by value (TASK-3462, codex r1)
* fix: on the applier path the built-in seed is recorded only after the apply confirms; a library change that only drops a field is offered (TASK-3462, codex r2)
* fix: a field the library added that the user already set reads diverged; an update clears convention metadata the library dropped (TASK-3462, codex r3)
* test: the lifecycle test finds the imported item by slug (the copy shares its title); ScanNUL's cost figures count the two new columns (TASK-3462)
* test(e2e): Library activate posts the entry to /library/activate and the item records its built-in origin (TASK-3462)
xarmian
c17865462f