feat(structure): remove dynamic toggle labels from table editor checkboxes (#8148)

[lxk955]

Summary

Closes #8148

When editing table structures and indexes, checkboxes for nullable (fields tab), unique (indexes tab), and concurrent (indexes tab) had dynamic text labels (是 / 否 via t("structureEditor.yes") : t("structureEditor.no")) that morphed between "Yes" and "No" upon toggling. In a tabular grid where the column header already specifies the attribute ("Nullable", "Unique", "Concurrent"), flipping text labels beside the checkboxes is counterintuitive and visually inconsistent with other columns such as Primary Key.

Changes

• In TableStructureEditor.vue:
  • Removed dynamic <span>{{ ... ? yes : no }}</span> labels from the nullable column in the columns table, centering its cell and header to match the Primary Key column.
  • Removed dynamic <span>{{ ... ? yes : no }}</span> labels from the unique and concurrent columns in the indexes table, centering their cells and headers.
  • Added appropriate aria-labels to the checkbox inputs for accessibility.
• In TableStructureEditor.metadataRevalidation.spec.ts:
  • Added a regression unit test verifying that the checkboxes do not render dynamic yes/no text spans upon toggling.

Verification

• Tested with pnpm test apps/desktop/src/components/structure/__tests__/TableStructureEditor.metadataRevalidation.spec.ts (all 42 tests passed).
• Tested concurrent transition, column selection copy, and primary key test suites (all passed).

[t8y2]

维护者补丁（bce848256，基于 c23d5f4）：为列表格的 primaryKey 复选框补上 :aria-label="t('structureEditor.primaryKey')"，与本 PR 为 nullable 复选框建立的「裸复选框 + aria-label」模式保持一致（该 key 全部 12 个语言文件均已存在）。

核验：TableStructureEditor.metadataRevalidation.spec.ts（42 用例）、columnSelectionCopy / concurrentTransition spec（9 用例）全部通过，oxfmt 格式检查通过。其余审阅结论不变，CI 跑完后即可合并。

[t8y2]

Thanks for the contribution! Merged in 7e324bd, will be released in the next version.