fix: preserve interleaved named-list fill positions - #1298

Purpose of the pull request

Fixes #1295.

Alternating pages between named template lists can overwrite a lower list's existing records after an upper list inserts rows. Preserve each list's append position so every supplied record survives.

What's changed?

• Use identity keys for the fill executor's per-cell position and style caches. Moving a template row no longer invalidates a cached AnalysisCell lookup; the public equality contract remains unchanged.
• Track the last filled row and column separately and move affected positions with the worksheet rows. This preserves vertical append cursors and horizontal lists below an expanding section, while leaving other sheets alone.
• Add real-workbook regressions for interleaved and ordered pages, filling lower lists first, horizontal lists, styles, row heights, scalar footers, and sheet isolation across XLS/XLSX and both memory modes.
• Document interleaved pagination in the English and Chinese fill guides.

Validation on JDK 25 (project Java 8 target):

• On the unmodified production code, 12 of the 20 new regression cases fail by overwriting previous records; the eight controls pass. All 20 pass after the fix, along with 19 existing fill tests.
• ./mvnw clean package -pl fesod-common,fesod-shaded,fesod-sheet: 1,869 tests, zero failures, errors or skips. No test groups excluded; the normal Jazzer seed regressions ran, rather than a timed fuzz campaign.
• The original issue's independent POI-reopen probe passes all eight ordered/interleaved format/memory combinations.
• Repository-wide spotless:check, Hawkeye 7.0.0 check, and git diff --check pass.
• All 135 website Markdown files pass the same markdownlint-cli2 0.24.0 / markdownlint 0.42.0 configuration used by Docs CI.

Checklist

• I have read the Contributor Guide.
• I have written the necessary doc or comment.
• I have added the necessary unit tests and all cases have passed.

Local validation used the JDK25 runtime and isolated Maven cache/temp directories. The remote JDK8/11/17/21/25 matrix, website build and timed fuzz campaign remain for CI or separate validation.

Generated-by: AI