Release v1.75.0

Promotion-only on top of v1.75.0-beta.1: seven version sources, the
generated bundle snapshots and the release metadata. No product source
code moves in this commit.

The line aggregates from the stable v1.74.0 and carries one user-visible
fix. The House Plan sidebar page could serve a previous version of the
card for hours: the panel entry fetched it through `./houseplan-card.js`,
a relative specifier, and relative resolution does not inherit the `?v=`
a dashboard gets from its Lovelace resource, while the entry files carry
no Cache-Control at all. The panel now imports the implementation by its
content-hashed name, so either the matching card arrives or the panel
says out loud that the page is stale (#535). Internal in the line: #536.

Known contradiction, recorded rather than silenced: the release contract
in scripts/release-contract.mjs requires the grouped "small fixes"
bullet unconditionally, while `npm run release:notes -- v1.75.0
--verify` rejects it because every user-visible issue of the range is
already itemised. The two rules deadlock any stable with a single
user-visible issue. The bullet stays, because the contract is the
automated gate that Validate enforces; the verifier's objection is
written down in STATUS and will get its own issue.

npm test 2532/2531/0 fail, release contract green on all seven sources,
docs strict green.

Issue: #535
User-Visible: yes
Release: v1.75.0

src/houseplan-card.ts

@@ -417,7 +417,7 @@ import type { MarkerRoomReferenceSnapshot } from './room-reference-transaction';
 import { SummaryRuntimeSlot, summaryRuntimeLoader } from './summary-runtime-loader';
 import { displayVersion } from './card-version';
 
-const CARD_VERSION = '1.75.0-beta.1';
+const CARD_VERSION = '1.75.0';
 const ENTRY_BUILD_FINGERPRINT = '__HOUSEPLAN_SOURCE_FINGERPRINT__';
 const EDITOR_RETRY_ASSET = '__HOUSEPLAN_EDITOR_RETRY_ASSET__';
 const ISO_RETRY_ASSET = '__HOUSEPLAN_ISO_RETRY_ASSET__';

src/houseplan-editor-runtime.ts

@@ -388,7 +388,7 @@ import {
   rewriteMarkerRoomReferences, type MarkerRoomReferenceSnapshot,
 } from './room-reference-transaction';
 
-const CARD_VERSION = '1.75.0-beta.1';
+const CARD_VERSION = '1.75.0';
 
 // #474: the editor imports the furniture artwork statically and hands it to
 // the page runtime the moment this chunk evaluates — before the loader's