[Bug] Docs examples for Flink actions, Spark bucketed join and JDBC lock are out of date #10996

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Paimon version
master @ f962939

Compute Engine
Flink, Spark

Minimal reproduce step

1. flink/action-jars.md: compact --path <TABLE_PATH> fails because ActionFactory.createAction() rejects --path since [flink] make warehouse in Flink action optional #4728.
2. maintenance/manage-snapshots.mdx: the expire_snapshots action example passes --identifier, so it fails with Argument 'database' is required.; --version is not read at all.
3. primary-key-table/query-performance.md, append-table/bucketed.mdx, learn-paimon/scenario-guide.mdx: the bucketed join setup only enables V2 bucketing; since [spark] Make bucket-preserving scans opt-in and retain parallel read units #10076 Paimon also needs scan.preserve-data-grouping, otherwise the join keeps its shuffle.
4. flink/sql-ddl.md, spark/catalogs.md: JDBC lock support lists only MySQL and SQLite, but DistributedLockDialectFactory also supports PostgreSQL ([core] Support lock for postgres catalog (#4836) #5005).
5. Links in variant.mdx and filesystems.mdx return 404, and pypaimon/sql.md points to an unresolvable host.

What doesn't meet your expectations?
Copied examples should run and links should open.

Anything else?
Related: #4836.

Are you willing to submit a PR?

• I'm willing to submit a PR!