Align contacts with organization-wide access

[alex-w-99]

Decisions

• Contact access tools: Removed contact access listing, grant, and revoke tools because contacts are organization-wide and legacy access rows are not visibility authority; note access tools remain identity-scoped.
• SDK compatibility: Raised the SDK floor to 0.5.1 and pinned CI to the SDK 0.5.1 source revision so removed methods fail during validation rather than at runtime.

Changes

• Remove the three contact access tools from the catalog, tests, and documentation.
• Describe contact reads and mutations as organization-wide.
• Warn that contact changes affect the shared address book.
• Preserve note access tools and guidance.

Verification

• npm run typecheck against SDK 0.5.1 source
• npm test (631 passed)
• npm run lint

Related Changes

• SDK: SDK 0.5.1: add contact memory inkbox#119
• OpenClaw: Align contacts with organization-wide access openclaw-plugin#42
• Hermes: Align contacts with organization-wide access hermes-agent-plugin#70
• Claude Code: Align contacts with organization-wide access claude-code-plugin#44
• Codex: Align contacts with organization-wide access codex-plugin#25
• Registry lock resolution remains on 0.5.0 until SDK 0.5.1 is published; refresh it before merge.