#500 gave `_serverCfg` and `_layout` prototype accessors but left them in
`static properties`. Lit marks such a property `wrapped` and, on the FIRST
update, force-writes it into `changedProperties` with an `undefined` old
value even though nobody assigned anything (`reactive-element.js:249-252`
and `:880-886`). `willUpdate` reads that as a config replacement, raises
`_cfgEpoch`, the memoized model key changes, and a 60-room house builds and
paints its model a second time: measured 19 update cycles, 4 builds and 4
epochs against 18 / 3 / 3 before #500, worth ~550 ms of `modelReadyMs` and
the same on `firstStableRenderMs` (3355 against a 3000 ceiling).
The declaration goes; the bodies stay reactive through the owner —
`_adoption` → `onBodyReplaced` → `requestUpdate(field, previous)` — which
needs no declaration: `getPropertyOptions` falls back to the default and
`changed.has('_serverCfg')` works as before. `noAccessor: true` would not
help, `wrapped` is set before that flag is read. The trap is written above
`static properties`, where someone would put the declaration back.
`cache.entries.cleanFloor` returns to 100 in both interaction budgets: the
120 entries were the extra epoch re-keying the per-room cache, not a
property of the design — the reasoning in 914e8402 was wrong.
Witness: test/config-adoption-ownership.test.mjs pins that neither body is
declared; the mutant `adoption-bodies-declared-reactive` puts the
declaration back and reddens it.
The boot diagnostics of the previous three commits touch four private
members, so they are declared in the performance contract: `_buildModel` and
`_cfgEpoch` outright (both exist in every supported comparison base), and the
adoption entry point as a current/legacy pair — #500 turned the private
`_adoptStructuralResponses` into the public `_adoptAuthoritative`, and an
undeclared rename would have the counter report zero adoptions instead of
failing.
The same commits carried a `node_modules` symlink: `.gitignore` had the
pattern with a trailing slash, which does not cover a symbolic link, and
`git add -A` in a sandbox worktree committed it. The link is removed and the
pattern loses the slash; a mutant run on this branch failed with `EEXIST` on
it.
Issue: #520
User-Visible: no
`test/config-adoption-ownership.test.mjs` pins identity writes to the owner
and ratchets body staging (AC1/AC2). `demo/smoke_post_write_adoption.mjs`
drives space/delete (both runtimes), Optimize Undo and Import apply with a
concurrent backdrop change between the write and the re-read (AC4). Smokes
that seed revisions from outside the card keep working through the
`seedIdentity` harness seam behind the card's delegate setters. The initial
View ceiling is re-centred with the measured fact; ARCHITECTURE.md gets the
boundary paragraph.
Issue: #500
User-Visible: no
Claude