all: update forms, inputs, and autocomplete to mdc components

[paulbert]

Update script grouped together FormField, Autocomplete, Input, and Select (probably because they are very similar and may share some styles). This changes inputs and form fields quite a bit.

A couple of initial observations:

• The markdown textbox shouldn't have that background. I think I added CSS to remove the form fields styles from this before, so hopefully I can just edit that and it'll be OK again.
• Form fields generally take up more space, so we may need to adjust some of the layouts (top bar on voices page stands out for this).
• Placeholder text only shows up when the field is empty right now. I'll check to see if adding a label isn't too hard.
• I think there's extra padding now making less of the text visible when there is overflow on a field (i.e. the title of a resource)
• There are two options for how a field is styled, the default "fill" or a simpler "outline" (shown below in the resource title). Not sure which I like better. Fill is a little more minimal, but the color change stands out vs outline which maintains the white background.

[paulbert]

On the missing labels:

From https://v15.material.angular.dev/guide/mdc-migration

We'll need to update all placeholders to use mat-label. Hopefully translations will transfer over after doing that.

[paulbert]

Resources form with labels