feat(ui): add LoRA support to SDXL linear UI

[psychedelicious]

What type of PR is this? (check all applicable)

• Feature

Have you discussed this change with the InvokeAI team?

• Yes
• No, because:

Description

Adds SDXL LoRA support in the Linear UI.

• new graph modifier addSDXLLoRasToGraph() handles adding LoRA to the SDXL t2i and i2i graphs.

QA Instructions, Screenshots, Recordings

1. Download and install https://civitai.com/models/118653?modelVersionId=128752 (per author, this only modifies UNet, and needs to be used with weight 2)
2. Restart server
3. Navigate to t2i tab
4. Write a simple prompt with oil painting in the name with manual seed, generate
5. Add the LoRA with weight 2, generate
6. Confirm the results are much more oil-painting-y
7. Generate an image without oil painting in the prompt, without LoRAs, to be used as init image
8. Navigate to i2i tab
9. Select the image from step 7 as init image
10. Add oil painting to prompt, change seed (to avoid fried images), generate
11. Add the LoRA with weight 2, generate
12. Confirm the LoRA'd result is much more oil-painting-y than the non-LoRA'd result

Expected Outputs

t2i without LoRA

t2i with LoRA

i2i init image

i2i without LoRA

i2i with LoRA

(freaking awesome LoRA btw, LOOK AT THOSE KITTIES)

[hipsterusername]

Dope cats!