Add local AgentRegistryGrant resolver

[mdheller]

Summary

Adds a deterministic local Agent Registry grant resolver for bootstrap dry-run flows.

Changes:

• Adds src/agent_machine/agent_registry.py.
• Adds scripts/resolve-agent-registry-grant.py.
• Adds scripts/validate-agent-registry.py.
• Adds agent-machine registry resolve ... through Python and bootstrap CLI delegation.
• Allows activation evaluation to use a resolved local grant from --grant-dir / --grant-file.
• Adds validate-agent-registry to make validate.
• Updates package validation to import agent_machine.agent_registry.
• Adds docs/architecture/agent-registry-grant-resolution.md.
• Links AgentRegistryGrant resolution from docs/index.md.

Validation

Canonical validation remains:

make validate

Production note

This is a deterministic local-store resolver only. A real Agent Registry endpoint/client remains a later production-hardening task.

[mdheller]

Partial supersession note: this PR is not discarded.

Core AgentRegistryGrant resolver payload was replayed and merged through #50.

Merged replacement commit: a13674a38083584ed764bfb2d469d326ce4f09b3

#50 carried forward:

• src/agent_machine/agent_registry.py
• scripts/resolve-agent-registry-grant.py
• scripts/validate-agent-registry.py
• docs/architecture/agent-registry-grant-resolution.md

Residual integration still to capture:

• Makefile validate-agent-registry target and top-level validate wiring
• bootstrap CLI registry delegation
• Python CLI registry resolve command and activation grant-store args
• docs index link
• package validator import/check

Residual issue: #51

Do not close this PR until #51 is resolved or explicitly linked as complete capture.

[mdheller]

Capture progress update.

#30 remains open and is not discarded.

Captured so far:

• Replay AgentRegistryGrant resolver core #50 / a13674a38083584ed764bfb2d469d326ce4f09b3: core local AgentRegistryGrant resolver module, resolver script, validation script, and architecture doc.
• Wire AgentRegistryGrant validation target #52 / a60ee5d51d0dfa8c173193fdd456bf5d5cb544f9: Makefile validate-agent-registry target, top-level make validate wiring, and docs index pointer.

Residual issue #51 remains open for:

• bootstrap CLI registry delegation.
• Python CLI registry resolve command.
• activation evaluation grant-store args.
• package validator import/check.

Do not close this PR until #51 is resolved or explicitly linked as complete capture.