docs: Address all remaining CodeRabbit nitpicks

- Add language specifier to checklist code block in SPEC
- Grammar fix: "AND" → "and" in P1 bug doc

SPEC_ARCHITECTURAL_DEBT.md

@@ -313,7 +313,7 @@ async def test_paid_tier_synthesis():
 
 Before merging ANY refactoring PR:
 
-```
+```text
 [ ] make check          # All 318+ unit tests pass
 [ ] make smoke-free     # Free Tier produces real synthesis
 [ ] make smoke-paid     # Paid Tier works (if you have key)

docs/bugs/P1_NO_SYNTHESIS_FREE_TIER.md

@@ -45,7 +45,7 @@ The `with_standard_manager()` in Microsoft Agent Framework uses the provided cha
 
 ### Secondary Issue: Duplicate Complete Events
 
-Both `MagenticFinalResultEvent` AND `WorkflowOutputEvent` are emitted when the workflow ends. The previous code handled both, yielding "Research complete." twice.
+Both `MagenticFinalResultEvent` and `WorkflowOutputEvent` are emitted when the workflow ends. The previous code handled both, yielding "Research complete." twice.
 
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