refactor: remove tok types compatibility shim

Author: Patel230

ARCHITECTURE.md

@@ -246,7 +246,6 @@ type PipelineContext struct {
 | `skills/` | 5 Claude-style agent skills (`tok`, `tok-commit`, `tok-compress`, `tok-help`, `tok-review`) | `SKILL.md` per skill |
 | `benchmarks/` | Benchmark harness (run.sh + results.md template) | `run.sh` |
 | `evals/` | Prompt-compression eval | `pipeline-bench.sh`, `prompts/en.txt` |
-| `types/` | Deprecated compatibility shim that re-exports `hawk-core-contracts/types` (kept for existing importers) | `finding.go`, `severity.go` |
 
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