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.

tests/typing_surface/create_table.rs

@@ -1,4 +1,4 @@
-//! Matrix coverage for `create table T with pk [<col>:<type>[, ...]]`
+//! Matrix coverage for `create table T with pk [<col>(<type>)[, ...]]`
 //! (ADR-0005, ADR-0009).
 
 use crate::typing_surface::*;
@@ -73,7 +73,7 @@ fn after_pk_word_does_not_re_offer_pk() {
 }
 
 #[test]
-fn after_pk_space_with_col_name_typed_expects_colon() {
+fn after_pk_space_with_col_name_typed_expects_paren() {
     let schema = schema_empty();
     let a = assess_at_end("create table Customers with pk Code", &schema);
     assert!(matches!(a.state, InputState::IncompleteAtEof));
@@ -81,10 +81,10 @@ fn after_pk_space_with_col_name_typed_expects_colon() {
 }
 
 #[test]
-fn after_colon_expects_type_candidates() {
+fn after_paren_expects_type_candidates() {
     let schema = schema_empty();
     let a = assess_at_end(
-        "create table Customers with pk Code:",
+        "create table Customers with pk Code(",
         &schema,
     );
     assert!(matches!(a.state, InputState::IncompleteAtEof));
@@ -92,14 +92,14 @@ fn after_colon_expects_type_candidates() {
         &a,
         &["text", "int", "serial", "shortid", "bool"],
     );
-    crate::snap!("after_colon", a);
+    crate::snap!("after_paren", a);
 }
 
 #[test]
 fn create_table_with_explicit_pk_parses() {
     let schema = schema_empty();
     let a = assess_at_end(
-        "create table Customers with pk Code:text",
+        "create table Customers with pk Code(text)",
         &schema,
     );
     assert!(matches!(a.state, InputState::Valid));
@@ -110,7 +110,7 @@ fn create_table_with_explicit_pk_parses() {
 fn create_table_with_compound_pk_parses() {
     let schema = schema_empty();
     let a = assess_at_end(
-        "create table Memberships with pk UserId:int, GroupId:int",
+        "create table Memberships with pk UserId(int), GroupId(int)",
         &schema,
     );
     assert!(matches!(a.state, InputState::Valid));