feat(duckdb): Add transpilation support for SPACE function

[fivetran-amrutabhimsenayachit]

The transpilation of SPACE() to REPEAT() fails in DuckDB when the input argument is a FLOAT or DECIMAL type because DuckDB's REPEAT() function strictly requires the second argument (repeat count) to be of type BIGINT. SQLGlot currently transpiles SPACE(n) to REPEAT(' ', n) without adding the necessary type cast, causing runtime errors.
Fix: Added a custom space_sql method in the DuckDB dialect to wrap the count argument with CAST to BIGINT.

After Fix:

 python3 -c "import sqlglot; print(sqlglot.transpile(\"SELECT SPACE(5) AS space_integer, SPACE(3.7) AS space_float, SPACE(CAST(4.9 AS DECIMAL(10,2))) AS space_decimal, SPACE(0) AS space_zero, SPACE(NULL) AS space_null\", read='snowflake', write='duckdb')[0])" | duckdb
┌───────────────┬─────────────┬───────────────┬────────────┬────────────┐
│ space_integer │ space_float │ space_decimal │ space_zero │ space_null │
│    varchar    │   varchar   │    varchar    │  varchar   │  varchar   │
├───────────────┼─────────────┼───────────────┼────────────┼────────────┤
│               │             │               │            │ NULL       │
└───────────────┴─────────────┴───────────────┴────────────┴────────────┘

[github-actions]

SQLGlot Integration Test Results

Comparing:

• this branch (sqlglot:RD-1147757-space, sqlglot version: RD-1147757-space)
• baseline (main, sqlglot version: 28.6.1.dev103)

⚠️ Limited to dialects: snowflake, duckdb

By Dialect

dialect	main	sqlglot:RD-1147757-space	difference	links
duckdb -> duckdb	4003/4003 passed (100.0%)	4003/4003 passed (100.0%)	No change	full result / delta
snowflake -> duckdb	870/1481 passed (58.7%)	872/1481 passed (58.9%)	⬆ improved by 0.1%	full result / delta
snowflake -> snowflake	1473/1481 passed (99.5%)	1473/1481 passed (99.5%)	No change	full result / delta

Overall

main: 6965 total, 6346 passed (pass rate: 91.1%), sqlglot version: 28.6.1.dev103

sqlglot:RD-1147757-space: 6965 total, 6348 passed (pass rate: 91.1%), sqlglot version: RD-1147757-space

Difference: No change