Problem

Call sites for tiered storage are stripped. src/tiered, conn_tiered.c, and block_tier.c remain as unused runtime.

Change

Delete src/tiered/, src/conn/conn_tiered.c, and src/block_cache/block_tier.c. Drop them from dist/filelist, dist/filelist.bzl, and dist/modularity. Strip the remaining __wti_blkcache_tiered_open call in block_cache.c. Delete __wt_btree_switch_object and __wt_schema_open_storage_source if this deletion leaves them with no callers. Remove the deleted symbols from dist/s_funcs.list and regenerate prototypes.

Keep header types (WT_TIERED, WT_DHANDLE_TYPE_TIERED, bstorage). Keep dir_store, WT_STORAGE_SOURCE / add_storage_source, table/file tiered_storage= and tiered_object parse stubs, connection tiered_storage= parse + error-if-enabled, api_data.py flush_tier keys, and flush_tier stats. Keep objectid. Keep backup:export. Do not edit layered/disagg except unused WT_BUCKET_STORAGE args that can wait.

Test

Ninja Debug + Python. cd dist && ./s_fast. python3 ../test/suite/run.py test_tiered_deprecate. Do not restore old functional test_tiered*.py.