feat: support pg like parameters

Summarize the changes

• feat: support pg like parameters

Ensure that

• New code is covered by unit and integration tests.
• Related issues would be automatically closed with gitlab's closing pattern (Closes #1, #2).
• Public modules are documented (check the rendered version with cargo doc --open).
• (if PEST grammar is changed) EBNF grammar reflects these changes (check the result with railroad diagram generator.

closes #543 (closed)

Next steps

• Update sbroad submodule in picodata/picodata.
• (if EBNF grammar is changed) create a follow-up issue in picodata/docs.

doc/sql/query.ebnf

@@ -47,7 +47,7 @@ reference   ::= (table '.')? name
 value       ::= 'TRUE'
                 | 'FALSE'
                 | 'NULL'
-                | '?'
+                | parameter
                 | integer
                 | unsigned
                 | double
@@ -67,6 +67,7 @@ type        ::= 'ANY'
                 | 'TEXT'
                 | 'UNSIGNED'
                 | 'VARCHAR' ('(' length ')')?
+parameter   ::= '$' unsigned | '?'
 delete      ::= 'DELETE' 'FROM' table ('WHERE' expression)?
 insert      ::= 'INSERT' 'INTO' table ('(' name (',' name)* ')')? (values row | select )  ('ON CONFLICT' 'DO'  ('NOTHING' | 'REPLACE' | 'FAIL'))?
 update      ::= 'UPDATE' table 'SET' ( name '=' ((table '.')? name) (',' name '=' (table '.')? name)* ) ( 'FROM' '(' select ')' ( 'AS' name )? )? ( 'WHERE' expression )?