chore: promote public runtime registration

[XnLemon]

Summary

• promote public Runtime registration through the immutable Stack assembly
• pin the final main-reachable Core, SDK, and Samples revisions
• update the Core contract identity and Go module dependency
• validate the exact Register -> Discover -> Install -> Invoke -> Record assembly

Closes #14

NeKiro-project/nekiro-sdk-go#6, NeKiro-project/NeKiro-Samples#14, and NeKiro-project/NeKiro#119 are merged.

Final revisions

• Core: 212c2b749c7f6d69f9beb271bc4dc391d6c68a70
• SDK: d7e06dff6115a03a6ca90b01ec4e6a9a4a0b9e4b
• Samples: 699356ec9cacd5e01edc9ad868970f7125d78dc9

All three revisions were verified against their canonical main branches before this Stack update.

Local validation

• go run ./cmd/manifest-validator components.json
• go mod tidy
• go mod verify
• go build ./...
• go test -count=1 ./...
• go test -race ./...
• go vet ./...
• git diff --check

Local Docker was unavailable, so the source-free Compose check and exact backend/browser product acceptance were delegated to this PR's CI.

Product acceptance

Stack CI run 31531510804 passed against the exact final assembly:

• backend: passed in 3m44s
• browser: passed in 3m57s
• manifest, compose, quality, security, required: passed

The backend run built the pinned components and exercised secure Nacos publication, initial snapshot/watch discovery, Router-mediated invocation and nested lineage, Ledger recording, deregistration fail-closed behavior, and replacement recovery.

Fallback report

Fallback delta: removed 0, retained 0, added 0, net 0
Added fallback evidence: none

[XnLemon]

LGTM for the provisional assembly on current HEAD be9b24be6d5fdc6a89be3c01f9e36ff68b531889.

I re-reviewed manifest consistency, Core contract identity/module alignment, canonical commit reachability, and the dependency graph from Samples to the SDK/Core revisions. No implementation finding remains. Stack CI run 31530045581 passed backend, browser, manifest, compose, quality, security, and required checks against this exact assembly.

This PR should remain Draft and must not merge with PR-head pins. After SDK #6, Samples #14, and Core #119 merge, replace every provisional revision with its final main-reachable commit and rerun the same required acceptance.

中文

已复核 provisional assembly 当前 HEAD be9b24be6d5fdc6a89be3c01f9e36ff68b531889，LGTM。

我重新检查了 manifest 一致性、Core contract identity/module 对齐、canonical commit 可解析性，以及 Samples 到 SDK/Core revision 的依赖图。没有剩余实现问题。Stack CI run 31530045581 已针对这套精确装配通过 backend、browser、manifest、compose、quality、security 和 required。

该 PR 应继续保持 Draft，不能携带 PR-head pin 合并。SDK #6、Samples #14、Core #119 合并后，需要把所有 provisional revision 替换成最终 main 可达 commit，并重新运行同一套 required acceptance。

[XnLemon]

LGTM