SDKs 0.24.0: stable Actor and Site public IDs

Added

• Stable Actor and Site public IDs. Actor and Site list/detail models,
  nested Video Actor/Site models, favourites, ignored sites and their change
  payloads expose publicId. Video summaries expose sitePublicId alongside
  siteId. Actor IDs use A followed by at least eight decimal digits (for
  example, A00000043); Site IDs use S followed by at least six (for example,
  S000002). Larger numbers grow without truncation. These are strings; retain
  their prefix and leading zeroes.
• Actor and Site list search parameters accept exact public IDs. Retained
  merged Actor IDs resolve to the active canonical Actor. Existing Actor/Site
  rows are stamped by the migration so their IDs reach change-feed consumers.

Compatibility notes

• Existing GUID identities, routes, request bodies and status codes remain
  unchanged. Public IDs supplement the GUIDs.
• SiteChangeSiteDto.publicId is required but nullable: a Site deleted before
  numbering was introduced has no assigned public ID. Other catalogue public
  IDs are non-null in the API contract. The generated SDKs retain Kiota's
  optional model properties, so an older server omitting a field can still be
  read.

Packages: Python prdb-sdk==0.24.0, npm @prdb/sdk@0.24.0, NuGet Prdb.Sdk 0.24.0, Go github.com/prdb-net/prdb-sdk/go@v0.24.0.

Implemented in #71.