mpv, pw-cat: update page; mpv: add pt_BR translation (#11734)

* mpv: merge file and URL playing examples

* mpv: add screenshot example

* mpv: move speed range to placeholder

* mpv: add pt_BR translation

* mpv: translate or in pt_BR

Co-authored-by: Sebastiaan Speck <12570668+sebastiaanspeck@users.noreply.github.com>

* mpv: fix: moving pt_BR translation to common/

* pw-cat: add quality example

* mpv: replace url example with "url"

Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>

* mpv: use English versions of keys in pt_BR

Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>

* mpv, pw-cat: fix verb tenses and use relative path in screenshot

Co-authored-by: Isaac Vicente <isaacvicentsocial@gmail.com>

---------

Co-authored-by: Sebastiaan Speck <12570668+sebastiaanspeck@users.noreply.github.com>
Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>
Co-authored-by: Isaac Vicente <isaacvicentsocial@gmail.com>

pages/common/mpv.md

@@ -3,13 +3,9 @@
 > A audio/video player based on MPlayer.
 > More information: <https://mpv.io>.
 
-- Play a video or audio file:
+- Play a video or audio from a URL or file:
 
-`mpv {{path/to/file}}`
-
-- Play a video or audio file from a URL:
-
-`mpv '{{https://www.youtube.com/watch?v=dQw4w9WgXcQ}}'`
+`mpv {{url|path/to/file}}'`
 
 - Jump backward/forward 5 seconds:
 
@@ -23,9 +19,13 @@
 
 `[ <or> ]`
 
-- Play a file at a specified speed (0.01 to 100, default 1):
+- Take a screenshot of the current frame (saved to `./mpv-shotNNNN.jpg` by default):
 
-`mpv --speed {{speed}} {{path/to/file}}`
+`s`
+
+- Play a file at a specified speed (1 by default):
+
+`mpv --speed {{0.01..100}} {{path/to/file}}`
 
 - Play a file using a profile defined in the `mpv.conf` file: