MINOR: filters: Use global instance order for startup operations

MINOR: filters: Use global instance order for startup operations

Use the global instance order for operations that have no channel side:
explicit-configuration detection, lookup, defaults inheritance, enabling,
post-parsing, checks, initialization and deinitialization, including the
per-thread callbacks.

Every instance now appears exactly once in these traversals, including
request-only and response-only classes. This removes the request-first
ordering and the response-side duplicate suppression. Per-channel lists
remain independent for side-specific processing; stream attachment is not
changed by this patch.