Antalya 26.8: pr-2159: combined port of 10 PRs

[zvonand]

Dropped from this backport: the AI dropped these surfaces rather than pulling in a missing prerequisite. Reviewers: confirm each is genuinely optional.

• ci/tests/test_print_stacktraces.py budget tests — file deleted on antalya-26.8 by 3a69545

Changelog category (leave one):

• Experimental Feature

Changelog entry (a user-readable short description of the changes that goes to CHANGELOG.md):

Add experimental content-addressed storage (cas) for object-storage disks, which stores MergeTree parts as deduplicated blobs in a shared S3/GCS pool that multiple servers can mount, replicates by relinking existing blobs instead of copying them, and comes with lease-coordinated garbage collection, online integrity checks, SYSTEM CAS commands, system tables, clickhouse-disks tools, ALTER TABLE ... EXPORT PARTITION support and configurable mount lease timing. Also stop object-storage listings from parsing every listed key as a JSON command, which removes one thrown and caught exception per key on every object storage.
Add experimental content-addressed storage (cas) for object-storage disks, which stores MergeTree parts as deduplicated blobs in a shared S3/GCS pool that multiple servers can mount, replicates by relinking existing blobs instead of copying them, and comes with lease-coordinated garbage collection, online integrity checks, SYSTEM CAS commands, system tables, clickhouse-disks tools, ALTER TABLE ... EXPORT PARTITION support and configurable mount lease timing. Also stop object-storage listings from parsing every listed key as a JSON command, which removes one thrown and caught exception per key on every object storage (#2159 by @filimonov, #2300 by @filimonov, #2307 by @k-morozov, #2312 by @k-morozov, #2326 by @k-morozov, #2349 by @k-morozov, #2360 by @filimonov, #2384 by @filimonov, #2385 by @filimonov, #2393 by @filimonov).

CI/CD Options

Exclude tests:

• Fast test
• Integration Tests
• Stateless tests
• Stateful tests
• Performance tests
• All with ASAN
• All with TSAN
• All with MSAN
• All with UBSAN
• All with Coverage
• All with Aarch64
• All Regression
• Disable CI Cache

Regression jobs to run:

• Fast suites (mostly <1h)
• Aggregate Functions (2h)
• Alter (1.5h)
• Benchmark (30m)
• ClickHouse Keeper (1h)
• Iceberg (2h)
• LDAP (1h)
• Parquet (1.5h)
• RBAC (1.5h)
• SSL Server (1h)
• S3 (2h)
• S3 Export (2h)
• Swarms (30m)
• Tiered Storage (2h)

Combined port of 10 PR(s) (group pr-2159). Cherry-picked from #2159, #2300, #2307, #2312, #2326, #2349, #2360, #2384, #2385, #2393.

• [experimental] CAS (Content-addressed storage) over shared object storage for antalya-26.6 #2159 — [experimental] CAS (Content-addressed storage) over shared object storage for antalya-26.6
• CAS improvements #2300 — CAS improvements
• CAS: configurable mount lease timing #2307 — CAS: configurable mount lease timing
• CAS: doc for GC round #2312 — CAS: doc for GC round
• CAS: gc scheduler stop join race #2326 — CAS: gc scheduler stop join race
• MemoryWorker: use sanitizer info for allocated counter #2349 — MemoryWorker: use sanitizer info for allocated counter
• Fix the coverage build: unused variable in gtest_cas_throttling_gate.cpp #2360 — Fix the coverage build: unused variable in gtest_cas_throttling_gate.cpp
• CI: cap the RustFS blocking-thread pool on the CAS-S3 lanes and collect its log #2384 — CI: cap the RustFS blocking-thread pool on the CAS-S3 lanes and collect its log
• CI: lldb stack budget by build flavor, and keep lldb's JIT breakpoint out of the server #2385 — CI: lldb stack budget by build flavor, and keep lldb's JIT breakpoint out of the server
• Temporary workaround: do not probe object-storage listing keys as JSON #2393 — Temporary workaround: do not probe object-storage listing keys as JSON

[github-actions]

Workflow [PR], commit [e330851]