feat(checker): examples() and spec_files() carry the specification's files

A consumer of the checker crate needs no path into this repository.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HS8WZziDnyxunC23MUxrLp

target/debug/.fingerprint/chrono-b514d6c50fddb808/lib-chrono.json

@@ -0,0 +1 @@
+{"rustc":11835527281324007204,"features":"[\"alloc\", \"clock\", \"default\", \"iana-time-zone\", \"js-sys\", \"now\", \"oldtime\", \"serde\", \"std\", \"wasm-bindgen\", \"wasmbind\", \"winapi\", \"windows-link\"]","declared_features":"[\"__internal_bench\", \"alloc\", \"arbitrary\", \"clock\", \"core-error\", \"default\", \"defmt\", \"iana-time-zone\", \"js-sys\", \"libc\", \"now\", \"oldtime\", \"pure-rust-locales\", \"rkyv\", \"rkyv-16\", \"rkyv-32\", \"rkyv-64\", \"rkyv-validation\", \"serde\", \"std\", \"unstable-locales\", \"wasm-bindgen\", \"wasmbind\", \"winapi\", \"windows-link\"]","target":15315924755136109342,"profile":2579911162000070427,"path":15056562814600360222,"deps":[[5157631553186200874,"num_traits",false,7657157486456086504],[6557439603276904804,"serde",false,17897631817058807532],[16619627449254928351,"iana_time_zone",false,18422109055410631395]],"local":[{"CheckDepInfo":{"dep_info":"debug/.fingerprint/chrono-b514d6c50fddb808/dep-lib-chrono","checksum":false}}],"rustflags":[],"config":9396254390672932401,"compile_kind":0}