warmhub 0.15.0

Release changes

• feat(collections): Arc and Bond become ordinary Things under protected V2 Shapes (commit 50fec9ce2a8f)
• fix(collections): suppress the migrated Arc THING on replay and reserve Collection in Python (commit 171e5daabba7)
• feat(collections): the Collections V2 cutover with a legacy-sugar window (commit adaaa4fe53dc)
• feat(collections): classify inbound traversal by closure and add the aggregate roles (commit ca07faa123f0)
• feat(collections): make the collection router read the certificate closure (commit 74bf13faaf25)
• feat(collections): split the read kind and carry collections in the Python SDK (commit cae90e67bf42)
• fix(collections): carry the summary rename into whedge and the e2e-py suites (commit dc266e612abb)
• fix(collections): stop head and history claiming member facts they cannot see (commit 9c6752da5e8d)
• fix(sdk-py): decode collections on paged rows, not just on detail reads (commit f7bbfcab6364)
• feat(collections): put the member layout on the Shape and the facts on the row (commit be4d60df9499)
• test(collections): pin the layout ruling and the four review findings it touches (commit 102b6e20d7a2)
• fix(collections): finish the summary reshape in the two packages CI typechecks separately (commit 338faa58a7ea)
• chore(sdk): regenerate the conformance artifacts over main's retired contracts (commit 43e4ee9ef5c8)
• feat(export)!: carry Shape certificates as pinned wref strings (commit 30187cb8082e)
• fix(collections)!: name a foreign certifying Shape by its repository (commit 18478e45b47f)

Reconstructed from SDK release tags.