chassis-power: Create initial application

Create the new chassis power monitor application and a service file that
would start it. Make the new application available via a meson option.

Tested: Verified the service and application start with no errors.
```
root@p10bmc:~# systemctl status phosphor-chassis-power.service
● phosphor-chassis-power.service - Chassis Power Monitor
     Loaded: loaded
(/usr/lib/systemd/system/phosphor-chassis-power.service; enabled;
preset: enabled)
     Active: active (running) since Mon 2025-11-10 19:08:09 UTC; 4min 28s ago
 Invocation: 6f0cac0ee4e04066b68ba448aa2d7ccc
   Main PID: 549 (phosphor-chassi)
        CPU: 29ms
     CGroup: /system.slice/phosphor-chassis-power.service
             └─549 /usr/libexec/phosphor-power/phosphor-chassis-power

Nov 10 19:08:09 p10bmc systemd[1]: Started Chassis Power Monitor.

root@p10bmc:~# ps |grep chassis
  549 root     14928 S /usr/libexec/phosphor-power/phosphor-chassis-power
```

Change-Id: Ia0ab5bc6c578b8203f09feec9b6927059db0f883
Signed-off-by: Adriana Kobylak <anoo@us.ibm.com>
diff --git a/meson.build b/meson.build
index 9fe350c..7843cd3 100644
--- a/meson.build
+++ b/meson.build
@@ -112,6 +112,7 @@
 servicedir = systemd.get_variable('systemd_system_unit_dir')
 
 services = [
+    ['chassis-power', 'phosphor-chassis-power.service'],
     ['supply-monitor', 'power-supply-monitor@.service'],
     ['sequencer-monitor', 'pseq-monitor-pgood.service'],
     ['sequencer-monitor', 'pseq-monitor.service'],
@@ -200,6 +201,9 @@
 if get_option('regulators')
     subdir('phosphor-regulators')
 endif
+if get_option('chassis-power')
+    subdir('phosphor-chassis-power')
+endif
 if get_option('sequencer-monitor')
     subdir('power-sequencer')
 endif