Concentrate configuration content parsing in syntax::serial

Fixes some pages not having parsed input by making it much harder to
construct a config with unparsed text, which is something you basically
never want. The parsing now happens much earlier and consumers don't
need to remember to parse the configuration anymore.

Fixes a possible stack overflow due to parsing and configuration
depending on each other.

This commit also has dependencies updates and minor justfile tweaks.

.justfile

@@ -22,6 +22,14 @@ run-watch:
 
 alias w := run-watch
 
+# Apply basic assessments, build and run on changes
+[group: 'develop']
+assess-run-watch extra='false':
+    {{ watch_cmd }} {{ just_cmd }} lint test \
+        {{ if extra == "cover" { "cover-assess" } else { "" } }} run
+
+alias aw := assess-run-watch
+
 # Format all files
 [group: 'develop']
 format:
@@ -207,8 +215,8 @@ alias fb := full-build
 
 ## META
 
-[default]
-_default:
+[default, private]
+default:
     @just --list --unsorted --justfile {{justfile()}}
 
 export RUSTFLAGS := "-Dwarnings"