Implement UI inspired by Amazon Assistant

For the design of how to show the messages & bulles on DisMoi mobile, we can create a first version that mimics Amazon Assistant more or less exactly. This way, there is no need for us to create new designs and we can go straight to implementation 😎

Here are some examples of the screens from Amazon Assistant that we can implement on our side:

### Step 1: DisMoi circle appears
When the user lands on a URL where there is a contribution, the see the DisMoi circle with a little "teaser" text, just like on Amazon Assistant:

### Step 2: Details panel slides up
When the user taps on the circle or the teaser text bubble, they should see the "details panel", just like on Amazon Assistant:

### Step 3: Close or Interact
**Close**
The user can then click or swipe down to close the panel and go back to browsing normally.

**Interact**
They can also interact with the message the same way they do currently in the desktop browser when viewing the "detail view" of the bulle:
- Click on a link inside the bulle
- Upvote/downvote
- Delete (never show again)

### Styling
If we can implement the above steps in the exact style of Amazon Assistant, using our DisMoi colors and logo, then we can clean up the details specific to DisMoi later.

We need to figure out the accessibility piece. Let's put that in another issue.