Validate code tags for class and member references

This commit also adds means to manually disable warnings
in `code` tags where it's a false positive with the new
`skip-lint` attribute.

Warnings are now enabled on CI to prevent future errors.

doc/classes/PhysicsServer2D.xml

@@ -118,7 +118,7 @@
 			<return type="RID" />
 			<param index="0" name="area" type="RID" />
 			<description>
-				Returns the [RID] of the space assigned to the area. Returns [code]RID()[/code] if no space is assigned.
+				Returns the [RID] of the space assigned to the area. Returns an empty [RID] if no space is assigned.
 			</description>
 		</method>
 		<method name="area_get_transform" qualifiers="const">
@@ -486,7 +486,7 @@
 			<return type="RID" />
 			<param index="0" name="body" type="RID" />
 			<description>
-				Returns the [RID] of the space assigned to the body. Returns [code]RID()[/code] if no space is assigned.
+				Returns the [RID] of the space assigned to the body. Returns an empty [RID] if no space is assigned.
 			</description>
 		</method>
 		<method name="body_get_state" qualifiers="const">
@@ -827,7 +827,7 @@
 			<param index="2" name="body_a" type="RID" />
 			<param index="3" name="body_b" type="RID" default="RID()" />
 			<description>
-				Makes the joint a pin joint. If [param body_b] is [code]RID()[/code], then [param body_a] is pinned to the point [param anchor] (given in global coordinates); otherwise, [param body_a] is pinned to [param body_b] at the point [param anchor] (given in global coordinates). To set the parameters which are specific to the pin joint, see [method pin_joint_set_param].
+				Makes the joint a pin joint. If [param body_b] is an empty [RID], then [param body_a] is pinned to the point [param anchor] (given in global coordinates); otherwise, [param body_a] is pinned to [param body_b] at the point [param anchor] (given in global coordinates). To set the parameters which are specific to the pin joint, see [method pin_joint_set_param].
 			</description>
 		</method>
 		<method name="joint_set_param">
@@ -918,13 +918,13 @@
 			<param index="1" name="data" type="Variant" />
 			<description>
 				Sets the shape data that defines the configuration of the shape. The [param data] to be passed depends on the shape's type (see [method shape_get_type]):
-				- [constant SHAPE_WORLD_BOUNDARY]: an array of length two containing a [Vector2] [code]normal[/code] direction and a [code]float[/code] distance [code]d[/code],
-				- [constant SHAPE_SEPARATION_RAY]: a dictionary containing the key [code]length[/code] with a [code]float[/code] value and the key [code]slide_on_slope[/code] with a [code]bool[/code] value,
+				- [constant SHAPE_WORLD_BOUNDARY]: an array of length two containing a [Vector2] [code]normal[/code] direction and a [float] distance [code]d[/code],
+				- [constant SHAPE_SEPARATION_RAY]: a dictionary containing the key [code]length[/code] with a [float] value and the key [code]slide_on_slope[/code] with a [bool] value,
 				- [constant SHAPE_SEGMENT]: a [Rect2] [code]rect[/code] containing the first point of the segment in [code]rect.position[/code] and the second point of the segment in [code]rect.size[/code],
-				- [constant SHAPE_CIRCLE]: a [code]float[/code] [code]radius[/code],
+				- [constant SHAPE_CIRCLE]: a [float] [code]radius[/code],
 				- [constant SHAPE_RECTANGLE]: a [Vector2] [code]half_extents[/code],
-				- [constant SHAPE_CAPSULE]: an array of length two (or a [Vector2]) containing a [code]float[/code] [code]height[/code] and a [code]float[/code] [code]radius[/code],
-				- [constant SHAPE_CONVEX_POLYGON]: either a [PackedVector2Array] of points defining a convex polygon in counterclockwise order (the clockwise outward normal of each segment formed by consecutive points is calculated internally), or a [PackedFloat32Array] of length divisible by four so that every 4-tuple of [code]float[/code]s contains the coordinates of a point followed by the coordinates of the clockwise outward normal vector to the segment between the current point and the next point,
+				- [constant SHAPE_CAPSULE]: an array of length two (or a [Vector2]) containing a [float] [code]height[/code] and a [float] [code]radius[/code],
+				- [constant SHAPE_CONVEX_POLYGON]: either a [PackedVector2Array] of points defining a convex polygon in counterclockwise order (the clockwise outward normal of each segment formed by consecutive points is calculated internally), or a [PackedFloat32Array] of length divisible by four so that every 4-tuple of [float]s contains the coordinates of a point followed by the coordinates of the clockwise outward normal vector to the segment between the current point and the next point,
 				- [constant SHAPE_CONCAVE_POLYGON]: a [PackedVector2Array] of length divisible by two (each pair of points forms one segment).
 				[b]Warning:[/b] In the case of [constant SHAPE_CONVEX_POLYGON], this method does not check if the points supplied actually form a convex polygon (unlike the [member CollisionPolygon2D.polygon] property).
 			</description>