Addressed build warnings by resizing and compressing several bot logo
images that were significantly larger than necessary. The images were
resized to 256x256 and compressed to enhance overall performance and
reduce the distribution size, specifically:

- gemma-2b-it-logo.png & gemma-7b-it-logo.png from 2048x2048 to 256x256
- falcon-180b-logo.jpeg from 1024x1024 to 256x256

This change was made in response to build warnings about asset sizes
exceeding recommended limits. Since most logos in public/bots are
already 256x256 or smaller, adjusting the notably larger ones ensures
uniformity and optimizes performance.

Although lmsys-logo.png and spark-logo.png are also somewhat large,
resizing and compressing them did not offer any advantages in file size
reduction, so they were left unchanged.

Build log warning for context:
```
WARNING Compiled with 2 warnings 10:13:10 PM

warning

asset size limit: The following asset(s) exceed the recommended size limit (244 KiB).
This can impact web performance.
Assets:
fonts/materialdesignicons-webfont.0766edc9.eot (1.25 MiB)
fonts/materialdesignicons-webfont.fbaef2a9.woff2 (394 KiB)
fonts/materialdesignicons-webfont.e659bf56.woff (574 KiB)
fonts/materialdesignicons-webfont.714a4eee.ttf (1.25 MiB)
js/app.001036d0.js (608 KiB)
css/chunk-vendors.f38fd820.css (946 KiB)
js/chunk-vendors.0223b32a.js (2.72 MiB)
bots/falcon-180b-logo.jpeg (458 KiB)
bots/gemma-2b-it-logo.png (282 KiB)
bots/gemma-7b-it-logo.png (277 KiB)
```

Result:
```
public/bots/ernie-logo.png        | Bin 58762  -> 39612 bytes
public/bots/falcon-180b-logo.jpeg | Bin 468993 -> 53886 bytes
public/bots/gemma-2b-it-logo.png  | Bin 288702 -> 20031 bytes
public/bots/gemma-7b-it-logo.png  | Bin 283507 -> 18084 bytes
public/bots/vicuna-logo.jpeg      | Bin 53975  -> 32817 bytes
public/bots/you-logo.png          | Bin 44256  -> 41765 bytes
```