A load freed only the parsed trip's nodes (Json.free) and kept every string the parser made, because
a loader might keep one; free_all freed every string and every key, so on a tree a migration had
added a literal to (`Value.put(v, "sver", Value.str("2"))`) it freed the literal and aborted.
- The parser marks the string values it makes (JP_OWNED, in the node's otherwise unused num) and
interns object keys (a few names, never freed); free_all frees only marked strings, never keys,
and a list's spares too. A setter that gives a marked node other text (value_set_str/_strs,
value_into_str/_strs, value_become) frees the parser's text first. value_as_int / _as_float read a
string as 0 as before.
- ludic.base sv_str returns intern(...): every package load that keeps a text read from a section
(minimap labels, a Thing's look, photo tags and files, an effect's label, ...) holds its own copy.
Golden json_free_edited: parse, put a literal key and string in, set a string, keep an interned copy,
free_all - 1100 loads: the copy reads on and nothing grows (the toolchain before this aborts, 134).
Tests: ludic.save, base, settings, minimap, things, photo, effects; json_saves, value_list_regrow; the
36 ui examples.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>