Harden typed Content-Range parsing

[fewensa]

Summary

• Harden Content-Range parsing to trim HTTP OWS, reject invalid controls, separators, bounds, overflow, and duplicates, and keep canonical bytes formatting.
• Add focused protocol tests for satisfied, unknown-length, unsatisfied, canonical, and malformed Content-Range values.
• Document typed Content-Range behavior in the root and server READMEs.

Verification

• cargo fmt --check
• cargo test -p rttp-protocol range
• cargo test -p rttp_client test_response
• cargo test -p rttp-server metadata_facade --test metadata_facade
• cargo test -p rttp --test test_server_models content_range
• cargo test -p rttp --test metadata_facade
• cargo test -p rttp-workspace-tests sync_client_typed_all_unsatisfiable_ranges_map_to_server_416_response

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-12T11:00:35.153963Z	1535f86	PR opened

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