feat: implement initial chat command processing to add judgments

As detailed in previous commit with the unit-test (which now pass),
the regex is as follows :

    (?<candidate>[a-zA-Z]{1})(?<grade>[0-9]{1})

We have room to support more than 25 candidates or 10 grades in the future.
Right now, this is enough, let's move on !

addons/majority_judgment/providers/MajorityJudgmentAbstractJudgmentsProvider.gd

@@ -0,0 +1,13 @@
+extends Reference
+class_name MajorityJudgmentAbstractJudgmentsProvider
+
+
+# Abstract class for Judgment Providers
+# The job of the children is to emit the judgment_emitted signal.
+
+
+signal judgment_emitted(
+	author_identifier,  # String, unique per author (aka participant)
+	candidate_index,    # int
+	grade_index         # int (0 == REJECT, up to the grading size minus one)
+)

addons/majority_judgment/providers/MajorityJudgmentChatCommandJudgmentsProvider.gd

@@ -0,0 +1,34 @@
+extends MajorityJudgmentAbstractJudgmentsProvider
+class_name MajorityJudgmentChatCommandJudgmentsProvider
+
+
+# Command examples
+# ----------------
+# 
+# A0 B2 c0 D1
+# 
+
+
+func process_chat_command(author_identifier:String, chat_command:String):
+	var candidate_index := 0
+	var grade_index := 0
+	
+	var regex = RegEx.new()
+	regex.compile("(?<candidate>[a-zA-Z]{1})(?<grade>[0-9]{1})")
+	
+	var results = regex.search_all(chat_command)
+	if results:
+		for result in results:
+			var candidate_string : String = result.get_string('candidate')
+			var grade_string : String = result.get_string('grade')
+			
+			grade_index = str2var(grade_string)
+			candidate_string = candidate_string.to_upper()
+			candidate_index = ord(candidate_string) - ord("A")
+			
+			emit_signal(
+				"judgment_emitted",
+				author_identifier,
+				candidate_index,
+				grade_index
+			)

tests/commands.test.gd

@@ -22,6 +22,7 @@ func test_single_command():
 	do_test_single_command("A0", [0, 0])
 	do_test_single_command("B2", [1, 2])
 	do_test_single_command("e4", [4, 4])
+	do_test_single_command("E4", [4, 4])
 
 
 func do_test_single_command(command:String, expected:Array):