feat: system catalogs tweaks, feat: migrate FKs to bigint too

[levkk]

• feat: make how we handle system catalogs configurable, i.e. if you want to get info from all shards in one query, set system_catalogs = "sharded"
• feat: when migrating integer primary keys to bigint, handle foreign keys as well

[codecov]

Codecov Report

❌ Patch coverage is 89.95633% with 23 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
pgdog/src/backend/schema/sync/pg_dump.rs	92.10%	9 Missing ⚠️
pgdog-config/src/sharding.rs	0.00%	7 Missing ⚠️
pgdog/src/backend/replication/sharded_tables.rs	55.55%	4 Missing ⚠️
pgdog/src/frontend/router/parser/query/select.rs	92.10%	3 Missing ⚠️

📢 Thoughts on this report? Let us know!

[blacksmith-sh]

Found 1 test failure on Blacksmith runners:

Failure

Test	View Logs
pg_tests/TestShardedTwoPcAutoOnError	View Logs