docs: document SQLite batch migrations with views

[Ryota-Di]

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Fixes

Fixes: #1207

Description

Documents a SQLite limitation when using batch migrations with views that
reference the table being recreated.

During the "move and copy" workflow, the original table is temporarily
dropped before the replacement table is renamed. SQLite may reject the
rename when an existing view still refers to the temporarily missing table.

The documentation also notes that temporarily enabling
PRAGMA legacy_alter_table while the replacement table is renamed can be
used as a workaround.

Verification:

• git diff --check
• Sphinx documentation build with warnings treated as errors
• Reproduced the failure locally with SQLite 3.53.1
• Verified that temporarily enabling PRAGMA legacy_alter_table allows the
  batch migration to complete and leaves the referencing view usable

[sqla-tester]

Thanks! Issue #1207 is now marked code review in progress and no longer open for pull requests, so this pull request holds the review for it and another one won't land on top of your work. If this pull request is abandoned, a maintainer can put open for pull requests back on #1207 to reopen it to others.