[iliaal]

Rationale

Complete the API-reference correction for existing property contracts: six ExcelFormat getters/setters accept null to read without changing the value, while false remains a setter value. Correct two ExcelSheet parameter annotations and document getIndexRange() warning-plus-false behavior for negative indexes and, on 64-bit PHP, indexes above INT_MAX.

Only nine docblocks and the Unreleased documentation note change. Runtime, signatures and tests are unchanged.

Validation

• Fresh strict native build: PHP 8.4.26 NTS / LibXL 5.2.0.1 trial, -Wall -Wextra -Wimplicit-fallthrough -Werror; zero compiler diagnostics.
• Full PHPT suite: 254 passed, 7 skipped, 0 failed or warned (261 total).
• 90 native XLS/XLSX contract assertions passed: nullable alignment/boolean getters, explicit false setters, print gridlines, zoom, valid/missing/negative/overflow named-range indexes and exact warning severity.
• All 12 reference PHP files lint clean; non-comment PHP tokens unchanged; git diff --check passed. Independent review checked native macros, stubs and arginfo, including 32-bit wording.
• Remote tree e35e1bcaccc8a9468520db478400d76565728d8e matches the tested local index. Actual merge-tree against current master is clean; no sibling PRs.

Limitations

Local build used retained official headers/library and direct compiler invocation, not a fresh phpize/configure install. Seven license/platform skips are not passes; no local Windows, ZTS, sanitizer or performance claim. Exact-head CI completed successfully: Tests run 40156107945 and Windows Build run 40156107911, all 36 executed jobs passed. One release-upload job was intentionally skipped, not passed. The workflow-security scan is path-filtered out for this docs-only change.

Audited CI logs: PHP 8.4 Linux 252 passed / 9 skipped; PHP 8.4 ZTS 253 / 8; Windows PHP 8.4 x64 NTS 247 / 14; both ASAN lanes 250 / 9 plus two isolated tests passed. All inspected summaries have zero failures or warnings.