[codex] add workspace file previews and robust web downloads

[rowankid]

Summary

Adds workspace file previews and fixes web downloads for remote browser sessions.

• Add draw.io preview/edit/save support for workspace .drawio and .drawio.xml files.
• Add web previews for .docx and spreadsheet files using third-party viewers/parsers.
• Fall back to WebSocket file bytes for web downloads when no direct daemon download host is available.
• Extend workspace file content operations from 10s to 60s so larger preview/download/save operations can complete over relay or another machine's browser.

Root Cause

Cross-machine browser sessions cannot assume a direct local daemon download host. The previous web download path required a direct HTTP target, while previews and fallback downloads use readFile over the active WebSocket. Larger docx/xlsx/drawio files could also exceed the generic 10s correlated request timeout.

Validation

• npx vitest run packages/app/src/stores/download-store.test.ts --bail=1
• npx vitest run packages/server/src/client/daemon-client.test.ts packages/app/src/stores/download-store.test.ts --bail=1
• npm run format && npm run format:check
• npm run typecheck
• npm run lint
• npm run build:web --workspace=@getpaseo/app

Deployment

Cloudflare Pages production has been updated and verified to serve bundle _expo/static/js/web/index-039df1bc75b0910f36fae94c96de6032.js.

• Production: https://paseo-app-eef.pages.dev
• Deployment: https://937efaa0.paseo-app-eef.pages.dev