feat(core)!: unify rich results, canonical imports, and ordered injections for 2.0

[Brian Krabach (bkrabach)]

Tool results lose rich content across native and RPC boundaries, source validation can import a different module identity than runtime mounting, and combined hook injections can lose per-item lifetime and provenance. This carrier preserves rich results and canonical module identity, adds ordered context injections, and reconciles native session metadata, model pricing, precise usage cost, and asynchronous JavaScript hooks.

The complete changes from #103, #110, and #111 are included by Git ancestry on current main, including #112 typed module-load diagnostics. The CLI prerequisite microsoft/amplifier-app-cli#358 is merged at 409eb088.

Version and migration:

• The candidate is 2.0.0 because public Rust ToolResult protobuf conversions become fallible and public result/model struct literals gain fields.
• docs/MIGRATING_TO_2_0.md documents Rust caller changes, strict source identity, ordered injection ownership, native-wheel requirements, and CLI-first rollout. Existing Python/JSON callers may omit new optional fields.
• Native regression coverage exercises mixed durable/ephemeral injections, registry-bound provenance, batch validation before writes/budget charges, ordered persistence, and metadata preservation.
• The smoke runner now fails on every nonzero amplifier exit, including failures whose output does not match a known exception pattern.

Validation at head 35f7aaed5816c76fa698ae685649b51e3acd8cc9:

• All eight GitHub checks passed, including Python 3.11/3.12/3.13, native Node bindings, default/WASM Rust, formatting/Clippy, protobuf reproducibility, and CLA.
• Local native Core 2.0.0: 1,115 Python tests passed, 1 skipped; 523 default Rust unit/integration/doc tests passed; 70 Node tests passed; default, WASM, and Node Clippy passed. The complete WASM suite also passed before the version-only bump.
• All four Python protobuf stubs reproduce byte-for-byte. Mock smoke-runner process exits 0, 7, and 124 produce the expected success, failure, and timeout outcomes.
• CLI full suite passed in separate environments against published Core 1.6.1 and native Core 2.0.0: 2,412 passed, 45 skipped, 13 deselected, 1 expected failure each; 34 focused source/credential tests also passed with each version.
• Current Unified consumer boundaries: 77 passed, 1 skipped. The actual Unified 0.19.19 cache/diagnostic fixture passed all four entrypoints with zero model calls, including strict invalid-module metadata. These used an isolated native debug-wheel environment with explicitly reused qualified dependencies.
• A fresh Linux aarch64 release wheel built on Spark and passed pristine import checks plus the default Docker recipe smoke. The qualifying run used merged CLI 409eb088, Foundation c6b33a3b, and Core 2.0.0, exited 0, and completed the real recipe-author example. No CLI/Foundation local-source override or prompt change was used. The script used --skip-build immediately after the separate fresh Docker build of this exact source.

Release-wheel SHA256: 7494b52ba1342e8f9bb3d7409933b62216cc39edcbeb59305826f66261608a0e.

Local disk exhaustion and the first smoke run's pre-merge CLI resolution are retained in review evidence; the final qualifying build and smoke ran on Spark. This source merge does not tag or publish packages and does not claim an upgrade of any running host or worker.

[Brian Krabach (bkrabach)]

Combined-family landing receipt: this PR was merged at 4f53e0f666aa370ec7e579bf282b7a4b6c96fbbc after CLI companion microsoft/amplifier-app-cli#358 merged at 409eb088c8a0fea652315e4ea0dcec949672829d.

The reviewed head 35f7aaed5816c76fa698ae685649b51e3acd8cc9 and merged main have identical tree 6e33e97fb6330343e41e3ecfc86775a7195fbda5. Heads of #103, #110, and #111 are all ancestors of this carrier. GitHub marked those PRs merged through this inclusion; they were not independently merged into main.

All eight pre-merge CI checks passed. Additional combined-state evidence: 1,115 Python tests; 523 default Rust tests; 70 Node tests; full CLI 2,412 tests against both published Core 1.6.1 and native Core 2.0.0; current Unified boundaries 77 passed/1 skipped; actual Unified 0.19.19 four cache/diagnostic entrypoints 4 passed with zero model calls. Fresh Linux release-wheel pristine imports and the unmodified default recipe prompt passed with exit 0 using merged CLI 409eb088 and Foundation c6b33a3b.

The release wheel has SHA256 7494b52ba1342e8f9bb3d7409933b62216cc39edcbeb59305826f66261608a0e. Migration instructions are in docs/MIGRATING_TO_2_0.md. No version tag, package publication, or production installation was performed by this review lane.