[ci] Consolidate build and test passes

[joshlf]

Replace the build matrix's separate check, build, test, and UI steps
with a target-classified executor. Use an unfiltered Cargo test on
native targets while retaining explicit cross-target and codegen
ownership.

Forward the outer feature selection into recursive UI builds and
derive fixture cfgs from Cargo artifacts. Gate snapshots by supported
toolchain and normalize feature-dependent candidate counts.

Hosted validation reduced non-Anneal PR wall time from 5:32 on the
exact parent to 4:04, an 88-second (26.5%) improvement. A second
same-shape baseline gives a 58-second improvement; averaged, the two
baselines give 73 seconds (23%). The critical native cell fell from 298
to 205 seconds, with its Cargo passes falling from 199 to 83 seconds
(58%). Across the 60-cell matrix, aggregate runner time fell by 30:03
(17.3%).

Expand the CI policy checker across Cargo metadata, the fully-excluded
event matrix, executor plans, and cross-workspace protocols. Add
mutation tests so future target, feature, profile, UI, and codegen
drift fails closed.

Bootstrap pinned stable and nightly toolchains before the parallel
pre-push checks. This prevents fresh-runner Rustup component-download
races without serializing the actual checks.

---

• 👉 [ci] Consolidate build and test passes #3506
• 　  [ci] Parallelize Miri and harden feature coverage #3505
• 　  [ci] Keep read-only checks from rewriting lockfiles #3516
• 　  [ci] Make crate releases resumable #3515
• 　  [ci] Fail required gates closed on cancellations #3514
• 　  [ci] Separate testing from privileged publication #3513

Latest Update: v14 — Compare vs v13

📚 Full Patch History

Links show the diff between the row version and the column version.

Version	v13	v12	v11	v10	v9	v8	v7	v6	v5	v4	v3	v2	v1	Base
v14	v13	v12	v11	v10	v9	v8	v7	v6	v5	v4	v3	v2	v1	Base
v13		v12	v11	v10	v9	v8	v7	v6	v5	v4	v3	v2	v1	Base
v12			v11	v10	v9	v8	v7	v6	v5	v4	v3	v2	v1	Base
v11				v10	v9	v8	v7	v6	v5	v4	v3	v2	v1	Base
v10					v9	v8	v7	v6	v5	v4	v3	v2	v1	Base
v9						v8	v7	v6	v5	v4	v3	v2	v1	Base
v8							v7	v6	v5	v4	v3	v2	v1	Base
v7								v6	v5	v4	v3	v2	v1	Base
v6									v5	v4	v3	v2	v1	Base
v5										v4	v3	v2	v1	Base
v4											v3	v2	v1	Base
v3												v2	v1	Base
v2													v1	Base
v1														Base

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Branch

git fetch origin refs/heads/Gc6fh3xti3lzya244gwjign6h6lemoptz && git checkout -b pr-Gc6fh3xti3lzya244gwjign6h6lemoptz FETCH_HEAD

Checkout

git fetch origin refs/heads/Gc6fh3xti3lzya244gwjign6h6lemoptz && git checkout FETCH_HEAD

Cherry Pick

git fetch origin refs/heads/Gc6fh3xti3lzya244gwjign6h6lemoptz && git cherry-pick FETCH_HEAD

Pull

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.85%. Comparing base (f703560) to head (17b3a0a).

Additional details and impacted files

@@                        Coverage Diff                         @@
##           Ghjiwdkxk7bi3ag2zcvbf3jc2c5yyyafc    #3506   +/-   ##
==================================================================
  Coverage                              91.85%   91.85%           
==================================================================
  Files                                     20       20           
  Lines                                   6093     6093           
==================================================================
  Hits                                    5597     5597           
  Misses                                   496      496           

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