add thumbnail images to Landsat search results

[dthiex]

• Landsat 8-9 L2 should use the same as Landsat 8-9 L1 (USGS Explorer does the same so I suspect they don't have/generate preview images for L2)
• Landsat 7 ETM+ (L1/L2 should use the same images, example link: https://landsatlook.usgs.gov/gen-browse?size=thumb&type=refl&product_id=LE07_L1GT_007008_20000316_20200918_02_T2)
• Landsat 4-5 TM (L1/L2 should use the same images, example link: https://landsatlook.usgs.gov/gen-browse?size=thumb&type=refl&product_id=LM04_L1TP_118028_19850301_20200902_02_T2)
• Landsat 1-5 MSS L1 (example link: https://landsatlook.usgs.gov/gen-browse?size=thumb&type=refl&product_id=LM02_L1GS_097068_19810316_20200905_02_T2)

[dgostencnik]

Reusing L1 previews for L2 tiles will not work. USGS Explorer is able to do this as they are storing info about original tile (L1) for each L2 tile, while sh catalog service doesn't provide this info.

for example ID: LC09_L2SP_190031_20220603_20220605_02_T1

We could try to guess original id by replacing some substrings as file structure is quite well documented, but this also doesn't work very well, mostly because of change date (20220605 in above example) which can be different for L1 and L2.

Last option would be to make a request to catalog for each returned tile, but this will produce too many additional requests and it shouldn't be done as part of findTiles in sh-js.

I don't think it is worth bothering with any of this options.