codemods: renamed-css-export and table-column-width-props look mechanically decidable but are manual

[mfal]

Both entries describe AST edits with no type information or call-site judgment required:

• renamed-css-export (packages/codemods/src/migrations/renamed-css-export/entry.md): replace the import specifier @mittwald/flow-react-components/styles with @mittwald/flow-react-components/all.css. Same shape as password-tools-subpath-renamed, which already is a codemod.
• table-column-width-props (packages/codemods/src/migrations/table-column-width-props/entry.md): remove maxWidth from every TableColumn; omit width/minWidth where the literal value was null. Same category of unconditional-on-value attribute edit as accent-box-color-to-background-color and button-color-accent-to-success, both of which are codemods.

Proposal: add codemods for both, following the pattern of the existing rename/attribute-edit codemods.

Not verified against a real usage site in this repo (no TableColumn width props or flow-react-components/styles import currently exist here to test against) — worth double-checking edge cases (e.g. width={null} vs width={undefined}, JSX spread props) before shipping.