cat-log: drop the --force-remote option

[oliver-sanders]

Stop using the --force-remote option with cylc cat-log commands.

Requires:

• cat-log: infer --force-remote for --mode=list-dir if job.out not present cylc-flow#6596
• cat-log: infer --force-remote if log file not present locally cylc-flow#6597

Once these are done:

• --force-remote will not be necessary for filesystem listings (--mode=list-dir).
• --force-remote and --mode=tail can be replaced by --mode=auto for log retrieval.

Note, this will mean that log files for finished jobs will no longer be streamed. The UI might want some minor changes to better communicate the meaning of this. Perhaps change the dialogue that currently displays the "connected" message to read "following" to make it clearer.

See also #506