Basically a simple way to perform any command/property action from the
command line. This takes the exact same syntax as input.conf but not
including the key naturally. Potentially useful for weird properties
that don't map well to options (like ao-volume). Fixes#12353.
This enhancement makes it easier to create constant width property
expansions, useful for the `--term-status-msg`. Additionally, it changes
to `%f` printing with manual zero trimming, which is easier to control
than `%g`. With this method, we can directly specify precision, not just
significant numbers. This approach also avoids overly high precision for
values less than 1, which is not necessary for a generic floating-point
print function.
A new print helper function is added, which can be used with adjusted
precision for specific cases where a different default is needed. This
also unifies the code slightly.
This adds a command to escape ASS tags to remove code duplication
between sub/osd_libass.c, console.lua, osc.lua, stats.lua and any user
script that calls mp.create_osd_overlay().
A command is used instead of scripting functions so that all clients can
use this and not just use Lua and JS ones.
osd_mangle_ass() also interprets osd-sym-cc and osd-ass-cc/{0,1}, but
since they use invalid UTF-8 characters there is no risk of escape-ass
users using them by accident, like with any OSD message.
Always replacing \n with \\N in mangle_ass() even when it is not called
by escape-ass doesn't seem to cause any issue, but I made it conditional
anyway to avoid changing how all OSD messages are treated unnecessarily.
There was no way for scripts to know the current size of the terminal,
which is essintial if they want to provide a good user experience even
without a window.
Manually editing interface-changes.rst is a giant maintenance pain that
causes merge conflicts all the time. Stop doing that nonsense and
instead have changes be written to files in DOCS/interface-changes. Also
remove that one sentence in changes.rst because it's just not true.
