[kvlonge]

Shared groundwork for a second native dialect parser.

• Gap and Parsed move from sqlquack-syntax-postgres into sqlquack-syntax (modes::models), unchanged in shape; the Postgres crate re-exports them, so its public API is the same.
• The receipt checker maps each LocalParser to its verdict through local_verdict; the hidden parse-worker takes --parser <snowflake|postgres|none> instead of --postgres. A new dialect parser is one enum variant and one match arm.

No Snowflake path changes behaviour; the landing gate (check-ci, test-rust, Snowflake checker byte-identity with summary/stale, verify-recorded, results --against main, lineage) will be posted here.

[kvlonge]

Proof gate on the exact head dcefa3a7b05d980212871f22c960e73678c625b5 against main f2d93eec (its parent).

Step	Result
make check-ci	rc=0
make test-rust	rc=0
Snowflake checker, 10 commands + summary/stale, main vs head	939/941 outputs byte-identical; snapshot differs only in catalogue_commit and the Snowflake parser_tree id (sqlquack-syntax's tree changes with the added types), translation.err only in the binary path
summary/stale	[]
sqlquack verify with recorded results, libduckdb loaded	main and head both 12,033 cases, 0 failed; outputs byte-identical apart from paths
syntax-coverage results --against main's baseline	0 regressions, 0 other changes; results-baseline.json unchanged
Lineage diff	7,814 cases, lineage identical

Postgres figure unchanged: 1,384 of 1,555 forms (89.0%), 19,346 of 22,726 obligations, 0 problems (parser tree d95965e3; the tree id moves only because parse/models.rs left the crate).

Main has since moved; the landing re-merges main and re-gates the exact head.