Use optional CORS proxy

[warpech]

Implements #8

To do:

• [ ] deploy on the target subdomain
• [ ] add a cross-browser test for CORS (IE11, Safari)
• [ ] add a JavaScript, URL and Web Messaging API (with tests) to disable the proxy or change the proxy URL
• [ ] restore a disabled test

[github-actions[bot]]

File size report: ( 3b143e07d4a808bf32bb555662f8d94bf9170034 )

# HTML file sizes
-rw-r--r-- 1 runner docker 349K Oct 25 17:38 dist/sv/index.html
# JS bundle sizes
-rw-r--r-- 1 runner docker 1.3M Oct 25 17:38 dist/sv/legacy.vendors~embedsChartRenderer.d2c646a288cdac41d786.chunk.js
-rw-r--r-- 1 runner docker 1.3M Oct 25 17:38 dist/sv/modern.vendors~embedsChartRenderer.b52ca646421d5cce5595.chunk.js
-rw-r--r-- 1 runner docker 1.2M Oct 25 17:38 dist/sv/legacy.legacy.worker.7dad2ba3eede621e36b4.bundle.worker.js
-rw-r--r-- 1 runner docker 1.2M Oct 25 17:38 dist/sv/modern.modern.worker.30d8c437109fae38e994.bundle.worker.js
-rw-r--r-- 1 runner docker 543K Oct 25 17:38 dist/sv/legacy.SpreadsheetViewer.96ab321c466cade737e8.chunk.js
-rw-r--r-- 1 runner docker 406K Oct 25 17:38 dist/sv/legacy.main.678c442352ec6c94c04a.bundle.js
-rw-r--r-- 1 runner docker 393K Oct 25 17:38 dist/sv/modern.SpreadsheetViewer.82474cf264ce40fce1c6.chunk.js
-rw-r--r-- 1 runner docker 348K Oct 25 17:38 dist/sv/modern.main.4594fff184230c9f61e4.bundle.js
-rw-r--r-- 1 runner docker 122K Oct 25 17:38 dist/sv/legacy.vendors~CrashScreen~SpreadsheetViewer.33cedcb3109cab2c328f.chunk.js
-rw-r--r-- 1 runner docker 122K Oct 25 17:38 dist/sv/modern.vendors~CrashScreen~SpreadsheetViewer.f62361ae1679ddb71805.chunk.js
-rw-r--r-- 1 runner docker  72K Oct 25 17:38 dist/sv/legacy.vendors~SpreadsheetViewer.a7533cc9b18b87e0dac5.chunk.js
-rw-r--r-- 1 runner docker  72K Oct 25 17:38 dist/sv/modern.vendors~SpreadsheetViewer.dced838f6cfd35932e6c.chunk.js
-rw-r--r-- 1 runner docker  26K Oct 25 17:38 dist/sv/legacy.CrashScreen.093b97cbe76371564c54.chunk.js
-rw-r--r-- 1 runner docker  22K Oct 25 17:38 dist/sv/modern.CrashScreen.18b1e9e4f77452cedaa4.chunk.js
-rw-r--r-- 1 runner docker  13K Oct 25 17:38 dist/sv/legacy.embedsChartRenderer.3c9a28cb2fa9a4067ffe.chunk.js
-rw-r--r-- 1 runner docker 8.3K Oct 25 17:38 dist/sv/modern.embedsChartRenderer.69b5805c30430bc66cae.chunk.js
# CSS bundle sizes
-rw-r--r-- 1 runner docker 31K Oct 25 17:38 dist/sv/SpreadsheetViewer.9e038aabc7f9bfa77853.extracted.chunk.css
-rw-r--r-- 1 runner docker 19K Oct 25 17:38 dist/sv/dark.8f9746538022b0f2fc5f9c97ee20197d.css
-rw-r--r-- 1 runner docker 19K Oct 25 17:38 dist/sv/light.03ddf3efe02cef7120efa35f2a51850c.css
# Total size of HTML files, CSS bundles and JS bundles
7.5M    total

[warpech]

Closing because of inactivity