Language Server: Improve hovered symbol resolution, fix renaming bugs, implement reference lookup

Co-Authored-By: Ryan Brue <56272643+ryanabx@users.noreply.github.com>
Co-Authored-By: BooksBaum <15612932+booksbaum@users.noreply.github.com>

modules/gdscript/tests/scripts/lsp/shadowing_initializer.notest.gd

@@ -0,0 +1,56 @@
+extends Node
+
+var value := 42
+#   ^^^^^ member:value -> member:value
+
+func variable():
+	var value = value + 42
+	#!  |   |   ^^^^^ -> member:value
+	#   ^^^^^ variable:value -> variable:value
+	print(value)
+	#     ^^^^^ -> variable:value
+
+func array():
+	var value = [1,value,3,value+4]
+	#!  |   |      |   |   ^^^^^ -> member:value
+	#!  |   |      ^^^^^ -> member:value
+	#   ^^^^^ array:value -> array:value
+	print(value)
+	#     ^^^^^ -> array:value
+
+func dictionary():
+	var value = {
+	#   ^^^^^ dictionary:value -> dictionary:value
+		"key1": value,
+		#!      ^^^^^ -> member:value
+		"key2": 1 + value + 3,
+		#!          ^^^^^ -> member:value
+	}
+	print(value)
+	#     ^^^^^ -> dictionary:value
+
+func for_loop():
+	for value in value:
+	#   |   |    ^^^^^ -> member:value
+	#   ^^^^^ for:value -> for:value
+		print(value)
+		#     ^^^^^ -> for:value
+
+func for_range():
+	for value in range(5, value):
+	#   |   |             ^^^^^ -> member:value
+	#   ^^^^^ for:range:value -> for:range:value
+		print(value)
+		#     ^^^^^ -> for:range:value
+
+func matching():
+	match value:
+	#     ^^^^^ -> member:value
+		42: print(value)
+		#         ^^^^^ -> member:value
+		[var value, ..]: print(value)
+		#    |   |             ^^^^^ -> match:array:value
+		#    ^^^^^ match:array:value -> match:array:value
+		var value: print(value)
+		#   |   |        ^^^^^ -> match:var:value
+		#   ^^^^^ match:var:value -> match:var:value