docs: issue #61 workbook-level shape meta design update

[ssaattww]

Summary

• update issue ExcelTemplateのsheetのrepeat対応 #61 design to use workbook-level XML metadata in shape text
• fix shape naming rule to read only __workbook_meta on __sheet_meta
• sync design report and task/phase tracking with detailed phase/task breakdown

Notes

• this is a documentation/planning PR created first as requested
• implementation tasks are listed in tasks/tasks-status.md (R61-02..R61-08)

Refs #61

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: c3d66fb2f6

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[chatgpt-codex-connector]

Use implicit item scope for sheet name normalization

When a workbook-meta <sheet> has from but omits var, runtime defaults the loop variable to item, but this branch normalizes name with EmptyVariableNames. For a name like @item, ExcelTemplateExpressionNormalizer rewrites it to @(root.Item) instead of @(item), so repeated sheet names resolve against root data (or fail) rather than the current iteration item. This only appears when from is set and var is omitted, but in that valid format it produces incorrect sheet naming behavior.

Useful? React with 👍 / 👎.