Add sourceosctl reasoning inspection and validation commands

[mdheller]

Summary

Adds a read-only sourceosctl reasoning command group for Superconscious / SourceOS canonical reasoning artifacts.

Commands added:

sourceosctl reasoning validate <run-dir>
sourceosctl reasoning inspect <run-dir>
sourceosctl reasoning replay-plan <run-dir>
sourceosctl reasoning events <run-dir>

Included

• sourceosctl/commands/reasoning.py
• plugin routing in bin/sourceosctl
• canonical reasoning fixture set under tests/fixtures/reasoning/deterministic/
• tests/test_reasoning_cli.py
• validate-reasoning-cli Makefile target wired into make validate

Boundaries

• Read-only only.
• No network, model provider, credential, browser automation, or host mutation.
• Does not become the cognition loop.
• Validates/inspects SourceOS canonical artifacts emitted by Superconscious:
  • reasoning-events.sourceos.jsonl
  • reasoning-run.sourceos.json
  • reasoning-receipt.json
  • reasoning-replay-plan.json
  • reasoning-benchmark.json

Validation

Expected validation:

make validate
python3 -m unittest discover -s tests -v
python3 bin/sourceosctl reasoning validate tests/fixtures/reasoning/deterministic
python3 bin/sourceosctl reasoning inspect tests/fixtures/reasoning/deterministic

Advances #22.