agent: Add commentaries to examples and peer-monitor scenario

Change-Id: I3aae03770f302bfe043f7bf6070a99a0d56fcebc

test/agent/examples/active-agent.scm

 #!/usr/bin/env -S ./agent.exe -s
 !#
 
+;;; Commentary:
+;;;
 ;;; This is an example of an active agent.
 ;;;
 ;;; The active agent ensure that an account is created and then call its peer
 ;;; every minute.
+;;;
+;;; Code:
 
 ;;; We import here Jami's primitives.
 (use-modules
@@ -48,22 +52,29 @@ hang up after MEDIA-FLOW seconds and #t is returned.
         (set! continue #f)
         success))))
 
+;;; Change FIXME for the peer id you want to contact.
 (define peer "FIXME")
 
+;;; This will create your agent and wait for its announcement on the DHT (see
+;;; (agent)).
 (define agent (make-agent "bfbfbfbfbfbfbfbf"))
 
+;;; This will make you friend with the other peer.  You need to accept the trust
+;;; request within a certain amount of time (see (agent)).
 (make-friend agent peer)
 
+;;; You can change the value of MEDIA-FLOW and GRACE-PERIOD.
 (let loop ([account (account-id agent)]
            [media-flow 7]
            [grace-period 30])
-
   (make-a-call account peer #:media-flow media-flow)
 
+  ;; Disabling our account for GRACE-PERIOD.
   (jami:info "Disabling account")
   (account:send-register account #f)
   (sleep grace-period)
 
+  ;; Renabling our account and wait GRACE-PERIOD.
   (jami:info "Enabling account")
   (account:send-register account #t)
   (sleep grace-period)

test/agent/examples/passive-agent.scm

 #!/usr/bin/env -S ./agent.exe -s
 !#
 
+;;; Commentary:
+;;;
 ;;; This is an example of a passive agent.
 ;;;
 ;;; The passive agent ensure that an account is created and accept all trust
 ;;; requests and incoming calls.
-
+;;;
+;;; Code:
 
 (use-modules (agent)
              ((jami account) #:prefix account:)

test/agent/scenarios/peer-monitor/scenario.scm

 #!/usr/bin/env -S ./agent.exe --debug -e main -s
 !#
 
+;;; Commentary:
+;;;
+;;; This scenario is testing connectivity between two peers.  An active peer and
+;;; a passive peer.  The passive peer accepts all incoming trust request and
+;;; incoming calls.  The active peer will call the passive peer every minute,
+;;; disabling and re-enabling its account in between to force a new connection.
+;;;
+;;; Every peers in this scenario will synchronize at midnight UTC±00:00.  When
+;;; synchronizing, peers will have a grace period of one hour to change their
+;;; account' details.  After that, the scenario is resumed.
+;;;
+;;; The active peer also keep statistics about success rate and failure rate of
+;;; calls made during the day.  After synchronization, the active peer flush the
+;;; statistics of the day to the file `stats.scm`, which can be further analyze
+;;; using Guile.  The rates are then reset to zero for the next day.
+;;;
+;;; Code:
+
 (use-modules
  (ice-9 match)
  (ice-9 threads)