fix(core): resolve storage config aliases to canonical keys

[liwuhen]

Purpose

normalize_storage_config currently applies mirrored key pairs from a single
snapshot of the normalized properties. This cannot resolve aliases that require
more than one mirror step.

For Azure, underscore aliases are declared through a dotted intermediate key:

• azure.account_name → azure.account.name
• azure.account.name → azure.account-name

However, AzdlsConfig reads the hyphenated canonical key
azure.account-name. Because newly mirrored keys are not processed again,
azure.account_name is silently ignored. The same issue affects the other
declared Azure underscore aliases.

This change replaces symmetric mirroring with direct, ordered
alias → canonical mappings. It also defines deterministic precedence when
multiple forms are supplied:

1. An explicitly supplied canonical key
2. The first matching alias in declaration order

For Azure, dotted aliases are declared before underscore aliases, resulting in:

canonical > dotted alias > underscore alias

Brief change log

• Change normalize_storage_config from symmetric one-pass mirroring to direct
  alias → canonical resolution.
• Preserve an explicitly supplied canonical value.
• Resolve multiple aliases in declaration order.
• Map every supported Azure dotted and underscore alias directly to the
  hyphenated key read by AzdlsConfig:
  • account_name
  • account_key
  • sas_token
  • client_id
  • client_secret
  • tenant_id
  • authority_host
• Update the S3, COS, OBS, and GCS alias tables to follow the same directional
  mapping contract.

Tests

• Unit test test_azdls_config_parse_underscore_aliases
  (storage_azdls.rs): data-driven coverage for every declared Azure
  underscore alias and verification that each value reaches the corresponding
  AzdlsConfig field. Fails on the pre-fix code.
• Unit test test_azdls_config_alias_priority (storage_azdls.rs): verifies
  canonical keys take precedence over aliases and dotted aliases take
  precedence over underscore aliases.
• Existing storage configuration tests verify the directional alias conversion
  does not regress S3, COS, OBS, or GCS configuration parsing.
• Commands run locally:
  • CARGO_INCREMENTAL=0 cargo test -p paimon --features storage-azdls --lib storage_azdls
  • CARGO_INCREMENTAL=0 cargo test -p paimon --no-default-features --features storage-s3,storage-cos,storage-azdls,storage-obs,storage-gcs --lib io::storage_
  • cargo fmt --all -- --check
  • git diff --check

API and Format

No public API or persisted data format changes.

Supported external storage configuration aliases now resolve directly to the
canonical keys consumed by each backend. When multiple forms of the same
setting are supplied, precedence is deterministic: the canonical key wins,
followed by aliases in declaration order.

Documentation

No documentation changes required.

[QuakeWang]

LGTM