fix(resize-observer): preserve hydration ids for accessor targets

[everton-dgn]

createElementSize(accessor) returned early during SSR while allocating a target effect on the client. In Solid 2, that effect consumes a hydration child identifier, so subsequent elements received different keys and hydration left server-rendered nodes unclaimed.

Reserve the same effect identifier on the server without evaluating the target or accessing browser APIs. Preserve nullable dimensions and the browser observer lifecycle.

Add real SSR-to-client hydration coverage for accessor and direct-element targets, including server node identity and observer disposal, plus target replacement/removal and SSR safety tests. The shared hydration harness now exposes original nodes and disposes the hydrated root on cleanup.

Fixes #1060.

Validation:

• Baseline accessor hydration failed with mismatched keys; direct-element hydration passed. Both pass with the fix.
• Related client suites: 177 tests across 11 files; related SSR suites: 9 tests across 3 files.
• Package build, typecheck, lint and formatting passed.

Hydration uses real Solid SSR/hydrate with jsdom rather than a graphical browser. Existing shared-harness formatting and console-lint failures, and missing Babel declarations in a standalone strict harness typecheck, remain outside this patch. The package gates pass.

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Latest commit: 52673b2

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@solid-primitives/resize-observer	Patch

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