Grammar: with-pk column specs use name(type), matching add column

`create table … with pk` parsed column types as `name:type`,
while `add column` uses `name(type)`. Unify on the parens
form so column-type syntax is consistent across the DSL:

    create table T with pk id(serial), name(text)

Only `COL_SPEC` changes (`:` → `( … )`); `build_create_table`
reads columns by role, so it is unaffected. The `:` that
separates table from column in `add column` / `drop column`
is unchanged. Sweeps the test suite, the typing-surface
matrix (two `after_colon` cells renamed to `after_paren`,
4 snapshots regenerated), the friendly catalog's usage
templates, ADR-0009's example, and requirements.md.

1039 passing / 0 failing / 1 ignored; clippy clean.

src/dsl/command.rs

@@ -6,7 +6,7 @@
 //! (e.g. "table does not exist").
 //!
 //! The shape supports compound primary keys natively even though
-//! only the dedicated `with pk a:int,b:int` grammar exposes them
+//! only the dedicated `with pk a(int),b(int)` grammar exposes them
 //! today. Future grammar extensions (inline column specs, `set
 //! primary key`, junction-table convenience commands) emit into
 //! the same shape.