sequencing

We need some good graphics for the main sampler screen. This is where you can do rudimentary editing of the samples that are played in the sequencer.
There are two screens. The main screen with the controls:

• Volume (this one may be changed later)
• Speed (Playspeed. The sample also pitches up or down)
• Filter (in the middle the sound is unchanged, away from center it engages either hi-pass

It isn't obvious to users that a search result URL is stable (until deleted).

To make this more obvious, we should add an explicit
Share results section, with a "Copy URL to clipboard" text that does what it says

Example: https://docs.nextstrain.org/projects/nextclade/en/stable/user/algorithm/07-quality-control.html

https://github.com/nextstrain/nextclade/blob/ccf2a0429e239e29a20dd4da1148b908ed2d8515/docs/user/algorithm/07-quality-control.md?plain=1#L51

gets rendered as:

<img alt="Identification of private mutations" src="/docs/user/assets/algo_private-muts.png">

and the absolute