GeezerVison

Part of feldera/cloud#2136. Stacked on #7801 (cloud-2136-credentials).

A driver or client error can echo the connection string or the option value it was given, and a log line or a message can interpolate the error anywhere. This adds LibraryError, a wrapper whose Display and Debug are the sanitized text, so that whatever is in scope at a log line or a message is already safe; the raw error stays inside for classification only.

• feldera_types::library_error::LibraryError: wraps any std::error::Error or anyhow::Error; prints the error and its sources with the credential scrub and the secret registry applied; no source(), so an anyhow chain walker cannot reach the raw text; raw() and downcast_ref() for classification, which also find the original error behind an anyhow chain.
• The credential scrub moves from the manager to feldera_types::credential_scrub, shared by both sides, and now also covers librdkafka's Invalid value "<v>" for configuration property "<k>", with plain or escaped quotes; a value with no closing part cuts the text off. The manager module re-exports it and keeps the driver-grammar tests.
• The Postgres input, output and CDC connectors wrap the driver error at each call that returns it: connect, URI parsing, queries, rollback and the backoff classification. The connection monitor is generic over the error type, so the raw type crosses no signature.
• crates/connectors/clippy.toml disallows tokio_postgres::error::Error; the two classification functions carry an allow with the reason. The rule sees the type only where it is written, so it guards signatures; the wrap at each call is what keeps the raw text out of messages.

Not covered yet: errors from the etl replication library in the CDC connector, and the Kafka, Delta Lake, NATS, DynamoDB and S2 boundaries. They follow in the same shape; the docs say so.

Validation: 22 scrub and wrapper tests, 3 manager tests for the driver grammar, the Postgres connect and classification tests, including an end-to-end test through the real input and CDC connect paths where the driver echoes a password (pasted as an option name) and the error shows the secret reference instead. fmt and clippy clean with warnings denied. Negative validation, each fix broken on purpose: removing the CDC parse wrap or formatting e.raw() in the input connect error fails the end-to-end tests; boxing an anyhow error fails the downcast test; dropping the escaped-quote pass or the cut-off fails the Kafka test; Display printing the raw text fails four tests; a source() that exposes the raw error fails the chain-walker test; dropping one allow makes clippy report the raw type at the signature.