Generate Preview link responses and runtime metadata

[karim-alweheshy]

Why

Native target linking needs response files and runtime-policy metadata derived from prepared dependencies.

Scope

Generate static-library Preview link responses and runtime metadata using artifact discovery and dependency output groups. Public activation remains separate.

Dependency and landing boundary

This draft uses an integration-only diff base, preview-review-base-link-metadata, combining preview-review-09-link-policy, preview-review-10-link-artifacts, preview-review-11-output-groups.

Do not merge this PR into the integration base. Its prerequisites must land on main first; then retarget/reconcile this branch onto main and rerun validation. The temporary base keeps prerequisite code out of this review diff.

Validation

Validated the propagated PR candidate 7ee20d7f5222d0a1b33e343d42df03c0ddc04801 against its updated
integration diff base c87802fa9da195aab2fe085af055bc7af48250e2 using Bazel 9.2.0 and
DEVELOPER_DIR=/Applications/Xcode.app/Contents/Developer.

• Focused link-parameter processor Python tests: 46 passed (bytecode disabled).
• At the updated integration base c87802fa9da195aab2fe085af055bc7af48250e2: root tests plus generated
  documentation passed, 117/117; 0 executed, all test results cached.
• At PR candidate head 7ee20d7f5222d0a1b33e343d42df03c0ddc04801 against base c87802fa9da195aab2fe085af055bc7af48250e2: root tests
  plus generated documentation passed, 125/125; 0 executed, all test results
  cached (--jobs=2).
• Repository Buildifier check and whitespace checks passed at both candidate
  points.

DEVELOPER_DIR=/Applications/Xcode.app/Contents/Developer USE_BAZEL_VERSION=9.2.0 bazel --bazelrc=bazel_9.bazelrc --nosystem_rc --nohome_rc test --jobs=2 --test_summary=terse //... //docs:diff_test
DEVELOPER_DIR=/Applications/Xcode.app/Contents/Developer USE_BAZEL_VERSION=9.2.0 bazel --bazelrc=bazel_9.bazelrc --nosystem_rc --nohome_rc run //:buildifier.check

Testing and limitations

Regression tests accompany the changed behavior. Rerun the commands above on the stated base. These results validate this exact split, not arbitrary cherry-picks or a fresh Xcode Canvas render. Hosted CI is pending at publication. This PR alone is not a claim of complete native Preview support; end-to-end Canvas validation belongs to the assembled activation branch.