Documentation/rv: Add documentation about hybrid automata

Documentation/rv: Add documentation about hybrid automata

Describe theory and implementation of hybrid automata in the dedicated
page hybrid_automata.rst
Include a section on how to integrate a hybrid automaton in
monitor_synthesis.rst
Also remove a hanging $ in deterministic_automata.rst

Reviewed-by: Nam Cao <namcao@linutronix.de>
Reviewed-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lore.kernel.org/r/20260330111010.153663-6-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>