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.

Cargo.toml

@@ -38,6 +38,8 @@ keyword-idents = "warn"
 [lints.clippy]
 # levels: allow, warn, deny, forbid
 
+manual_non_exhaustive = "allow"
+
 # pedantic
 assigning_clones = "warn"
 borrow_as_ptr = "warn"
@@ -63,7 +65,6 @@ explicit_iter_loop = "warn"
 filter_map_next = "warn"
 flat_map_option = "warn"
 float_cmp = "warn"
-fn_params_excessive_bools = "warn"
 format_push_string = "warn"
 from_iter_instead_of_collect = "warn"
 if_not_else = "warn"
@@ -126,7 +127,6 @@ semicolon_if_nothing_returned = "warn"
 should_panic_without_expect = "warn"
 similar_names = "warn"
 str_split_at_newline = "warn"
-struct_excessive_bools = "warn"
 struct_field_names = "warn"
 trivially_copy_pass_by_ref = "warn"
 unchecked_time_subtraction = "warn"