fix: preserve statement boundaries after PostgreSQL routines

[minleejae]

PostgreSQL routines with AS '...' bodies can consume every following statement. For example, CREATE FUNCTION f() RETURNS integer AS 'SELECT 1;' LANGUAGE sql; SELECT 2; currently becomes one CreateFunction. Recognize the quoted body and stop at the declaration's terminating semicolon so the second statement receives its own AST.

Fixes #1994.

• Share body-literal capture between CREATE FUNCTION and CREATE PROCEDURE, preserving ordinary, escape and dollar-quoted text plus trailing routine options.
• Preserve the required newline between continued body strings when rendering the legacy declaration parts. Respect explicit E'...' escapes without enabling backslash escaping for ordinary strings.
• Keep parameter defaults and aliases inside unquoted routine blocks from being mistaken for the routine body boundary.
• Cover the issue's published function and qualified index example together with a following SELECT. PostgreSQL-specific syntax requires Dialect.POSTGRESQL.

The existing declaration-parts API remains in place. Routine bodies stay opaque: this does not validate PL/pgSQL source or expose its internal statements as an AST. The issue's abbreviated body is tested for preservation; executable PostgreSQL examples are checked separately.

Validation:

• 35 new regression-test executions covering statement counts and types, body preservation, toString and statement deparser round trips, consecutive routines/DDL, EOF, malformed quoting, trailing parse errors and existing unquoted routine behavior.
• Full Gradle check: 7,510 tests, no failures or errors, 25 skipped; grammar ambiguity, formatting and static checks passed.
• Maven clean verify: 7,492 tests, no failures or errors, 25 skipped.
• PostgreSQL 18.6: 22 valid routine examples executed as original SQL, toString output and visitor output (66 successful executions). The following statement ran in each case, and PostgreSQL's stored prosrc matched across all three forms.

Syntax references: CREATE FUNCTION, CREATE PROCEDURE, and string constants.

[manticore-projects]

Please resolve conflicts.

[minleejae]

@manticore-projects Thanks for flagging this!

Please resolve conflicts.

Merged the latest master and resolved the grammar conflict. This keeps master's dialect-specific escape-string handling while preserving the quoted routine body and following-statement boundaries.

The full Gradle check passes on Java 17: 7,764 tests, 0 failures/errors, 25 skipped, including the routine-boundary, PostgreSQL comment-literal, statement-list deparser, grammar ambiguity and static checks. GitHub reports no merge conflicts; CI is running on the updated head.

Commit: c52b59ad