acf_rendered_block() preview render leaks acf_setup_meta() state (no matching acf_reset_meta)

Description

The preview paths of acf_rendered_block() / acf_rendered_block_v3() call acf_setup_meta() for post-render validation but never call the matching acf_reset_meta(), leaving block-scoped local meta active after the function returns.

This compounds badly with how local meta works: while acf_setup_meta() is active for a post id, ACF_Local_Meta's pre_load_metadata filter returns __return_null for any meta name not present in the local set (includes/local-meta.php:194-203) — shadowing real database values for that post. So after a block preview render, unrelated get_field() calls for the same post id can silently return null.

Affected code

• includes/blocks.php (acf_rendered_block / acf_rendered_block_v3 preview paths)
• Interplay: includes/local-meta.php:194-203

Reproduction

Repro documented in #450: tests/php/includes/blocks/test-blocks-render.php (tear_down resets the leaked state manually and carries the NOTE comment); the shadowing behavior itself is characterized in tests/php/includes/test-local-meta.php (test_local_meta_shadows_missing_names).

Suggested fix

Pair every acf_setup_meta() in the preview/validation paths with acf_reset_meta() (try/finally semantics or immediately after the validation read).

Found during the 2026-06 test campaign (see PR #450).

Inspect the preview paths in includes/blocks.php, then read the local-meta interaction in includes/local-meta.php:194-203. Use tests/php/includes/blocks/test-blocks-render.php and tests/php/includes/test-local-meta.php as the starting checks. Done means preview rendering no longer leaves local metadata active, the regression tests pass, and the manual tear_down reset is no longer needed.