Attach the SQL-facing arity from the CREATE FUNCTION signatures

[estebanzimanyi]

The @sqlfn map gives each catalog function its MobilityDB SQL name, but the binding-facing arity is the SQL CREATE FUNCTION signature, not the wider C one. A SQL arg with a DEFAULT clause is optional, and a trailing C parameter absent from the SQL form is a C-only out-param (e.g. the size_t * of the *_as_hexwkb family). Without this a generator emits the raw C arity — trajectory(temporal, bool) instead of SQL trajectory(temporal), or asHexWKB(temporal, byte, <out>) instead of asHexWKB(temporal) — forcing every binding to hand-special-case the flag and out-params (which the codegen North Star forbids).

What

parser/sqlfn.py parses mobilitydb/sql/**/*.in.sql for CREATE FUNCTION name(args) ... AS 'MODULE_PATHNAME','<Wrapper>', keys by the wrapper (the @csqlfn target), and attaches per function:

• sqlArity — required SQL args (no DEFAULT)
• sqlArityMax — total SQL args (including DEFAULT)

so a generator derives: C params [0, sqlArity) required, [sqlArity, sqlArityMax) SQL-optional, [sqlArityMax, C-arity) out-params. run.py wires the mobilitydb/sql source root into the @sqlfn step.

On the current master surface: 2513 functions receive sqlArity/sqlArityMax; tpoint_trajectory → (1, 2), temporal_as_hexwkb → (1, 2) over its 3-param C signature (the size_out is the lone out-param).

Why now

The catalog previously lost this enrichment, so consumers that key UDF/binding arity off it regressed. Proven end-to-end: with this restored, MobilitySpark's generated trajectory UDF registers as the SQL-faithful UDF1 (was UDF2) and its suite goes green — with no hand special-case in the binding.