Automate PR creation to update Wallet Gateway OpenRPC sources

[danielporterda]

Summary

• expand the generated-reference source updater to select Wallet Gateway OpenRPC independently
• split generated-reference source update implementations into scripts/generated_reference_sources/, with typed config dataclasses for Splice OpenAPI and Wallet Gateway OpenRPC
• type each source config dataclass raw payload with source-specific TypedDict shapes, including nested Splice family/spec entries and Wallet Gateway spec entries
• move generated-reference PR git/GitHub helpers into scripts/generated_reference_pr_utils.py
• remove loose Any JSON handling from the new updater/summarizer code in favor of concrete source-config dataclasses, TypedDict payloads, and narrowed JSON mappings
• simplify docs-env execution so repo commands assume direnv exec; direct execution only happens after the script's own marked re-entry to avoid recursion
• keep .github/workflows/update-version-dashboard.yml as a thin Action wrapper that calls scripts/update_generated_reference_prs.py --targets all
• default generated PR base branch from the current checkout branch, with GITHUB_REF_NAME only as a detached-checkout fallback
• default generated PR repository through gh repo view, while still allowing --base-branch and --repository overrides for unusual local runs
• have each configured update target open/update its own draft PR branch instead of one combined PR
• add version-change summaries so generated PR bodies explain before/after version changes
• pass GitHub tokens through dashboard GitHub API requests to avoid unauthenticated rate limits
• keep this implementation PR free of generated OpenRPC output; generated docs should come from workflow-created PRs

Validation

• python3 -m pytest tests/test_docs_env.py tests/test_update_generated_reference_sources.py tests/test_update_generated_reference_prs.py tests/test_summarize_version_changes.py tests/test_generate_network_component_versions.py tests/test_wallet_kernel_nav.py tests/test_openrpc.py
• python3 -m py_compile scripts/docs_env.py scripts/generated_reference_pr_utils.py scripts/update_generated_reference_prs.py scripts/update_generated_reference_sources.py scripts/generated_reference_sources/__init__.py scripts/generated_reference_sources/common.py scripts/generated_reference_sources/splice_openapi.py scripts/generated_reference_sources/wallet_gateway_openrpc.py scripts/summarize_version_changes.py scripts/generate_network_component_versions.py scripts/generate_wallet_gateway_openrpc_reference.py
• python3 scripts/update_generated_reference_sources.py --help
• parsed .github/workflows/update-version-dashboard.yml with PyYAML
• python3 scripts/update_generated_reference_prs.py --help
• rg scan confirmed no Any remains in the PR-owned updater/summarizer/test files and no hidden GitHub repository env lookup remains
• git diff --check