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/serde_core-00412b0b600e3354/invoked.timestamp

@@ -0,0 +1 @@
+This file has an mtime of when this was started.

target/debug/.fingerprint/serde_core-00412b0b600e3354/lib-serde_core

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+f374c4a61a5cc969

target/debug/.fingerprint/serde_core-00412b0b600e3354/lib-serde_core.json

@@ -0,0 +1 @@
+{"rustc":11835527281324007204,"features":"[\"alloc\", \"result\", \"std\"]","declared_features":"[\"alloc\", \"default\", \"rc\", \"result\", \"std\", \"unstable\"]","target":6810695588070812737,"profile":2479888663174618594,"path":14396043232965050072,"deps":[[11029742160753049355,"build_script_build",false,7895303542109914569]],"local":[{"CheckDepInfo":{"dep_info":"debug/.fingerprint/serde_core-00412b0b600e3354/dep-lib-serde_core","checksum":false}}],"rustflags":[],"config":9396254390672932401,"compile_kind":0}