[release] 🔖 (examples): Bump pinned SDK versions to rc.4

[Chisanan232]

What changed

Bumps the shared SDK version source of truth (metadata/sdk-versions.yaml) from
rc.3 to the now-published rc.4 SDKs, and cascades the pin to every example
sub-project by regenerating downstream manifests.

• metadata/sdk-versions.yaml: python 0.0.1rc3 → 0.0.1rc4,
  node 0.0.1-rc.3 → 0.0.1-rc.4, go v0.0.1-rc.3 → v0.0.1-rc.4.
• Regenerated via python scripts/generate_example_metadata.py (no hand-edits):
  55 files rewritten — 18 pyproject.toml, 6 package.json, 4 go.mod,
  27 README.md bounded install blocks.
• Refreshed committed lockfiles to match (4 go.sum via go mod tidy,
  6 pnpm-lock.yaml via pnpm install --lockfile-only) — required so the
  frozen-lockfile / go test install paths in CI resolve the rc.4 SDK.
  Diffs are confined to the @agent-assembly/* packages.

The rc.4 packages are live on PyPI (agent-assembly==0.0.1rc4),
npm (@agent-assembly/sdk@0.0.1-rc.4), and the Go proxy
(github.com/ai-agent-assembly/go-sdk@v0.0.1-rc.4), so the example verify lanes
that install the published packages now resolve — this PR trails the publish
specifically so example CI goes green.

Related ticket

Closes AAASM-rc4

How to verify

• python scripts/generate_example_metadata.py → "No changes" (idempotent; the
  example-metadata-check.yml drift gate passes).
• Verified locally against the real rc.4 packages: go (go test ./... green for
  all 4 examples), node (custom-tool-policy frozen install + tsc + 7 vitest
  tests green), python (custom-tool-policy uv sync installs 0.0.1rc4,
  7 pytest pass).

Checklist

• PR title follows [AAASM-XXXX] <GitEmoji> (<scope>): <summary>
• No secrets, API keys, or .env files committed
• Example sub-projects include their own README.md with prerequisites and run instructions
• SDK/runtime version dependencies are documented or pinned

🤖 Generated with Claude Code

https://claude.ai/code/session_01Rk7iwwAuGv6HbwK8hY8Fbr

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[Chisanan232]

CI status: 46 pass / 3 fail (real rc.4 dependency-floor incompatibility)

All verify-go, verify-node, verify-scenarios and the metadata-drift gate are
green installing the real published rc.4 packages. Three verify-python
lanes fail — and they are a real defect, not something to skip or route
around (per this repo's Verification policy):

agent-assembly==0.0.1rc4 tightened its floors to pydantic>=2.13.4,<3 and
protobuf>=6.33.6,<8, which are unsatisfiable against the currently-published
framework releases these examples pin:

Lane	Conflict	Dep kind
autogen-tool-policy	autogen-core>=0.7.5 needs protobuf>=5.29.3,<5.30 vs rc.4 protobuf>=6.33.6	base
semantic-kernel-tool-policy	semantic-kernel>=1.36.0 (<1.42 caps pydantic<2.13; >=1.42 needs azure-ai-agents prerelease) vs rc.4 pydantic>=2.13.4	base
crewai-research-crew	crewai>=1.15.2 caps pydantic<2.13 vs rc.4 pydantic>=2.13.4 (surfaced via uv's universal-lock resolution)	live extra

On master (rc.3) these resolved — pydantic locked at 2.12.5. rc.4's raised
floors regressed compatibility, and there is no examples-repo fix: no
published autogen-core / semantic-kernel / crewai version satisfies rc.4's
constraints. The fix belongs upstream — either the SDK relaxes its
pydantic/protobuf floors, or those frameworks publish rc.4-compatible
releases. Holding this PR (not merging) until then.