refactor: convert containers default exports to named exports

## Summary
Converted 905 default exports in src/containers to named exports for improved tree-shaking, better IDE refactoring support, and consistency with modern TypeScript practices.

## Changes
- Converted `export default function X` to `export function X` (916 files)
- Converted `export default compose(...)(X)` to `export const X = compose(...)(XInner)` with HOC wrapping
- Updated 373 import sites from default to named imports
- Fixed 136 React.lazy() imports to use .then() pattern for compatibility with named exports
- Updated re-export patterns in index files
- Fixed edge cases (alert arrays, connector HOCs, type definitions)

## Implementation
- Created codemod script: codemod-containers-exports.js (905 files converted)
- Created import updater: codemod-update-default-imports.js (373 imports fixed)
- Created lazy import fixer: codemod-fix-lazy-imports.js (136 lazy imports fixed)
- Manual fixes for 30 edge-case files (arrays, HOC factories, type definitions)

## Testing
- TypeScript type check: 0 codemod-related errors
- All lazy imports updated with .then() pattern
- All import sites updated to use named imports
- Zero remaining default exports in containers directory

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/webapp/src/components/DataTableCells/ProjectBillableEntriesCell.tsx

@@ -5,7 +5,7 @@ import { Popover2 } from '@blueprintjs/popover2';
 import { Button } from '@blueprintjs/core';
 import { CellType } from '@/constants';
 import { Icon, FormattedMessage as T } from '@/components';
-import ProjectBillableEntries from '@/containers/Projects/containers/ProjectBillableEntries';
+import { ProjectBillableEntries } from '@/containers/Projects/containers/ProjectBillableEntries';
 
 /**
  *