validation: tip tooling no longer reads renamed source paths

Fixes the regressions from the entry/compiler renames (2b3c2a7, d318911)
that Astra reproduced at d318911:
- run_refined_dfg.verify_source: a manifest file missing from the checkout
  is a 'Source mismatch' (was FileNotFoundError); the current-checkout
  (Jet scenario) capture hashes the manifest's harness files plus the
  checkout's own 'git ls-files src', not historical src paths.
- time_window_dfg: candidate file list names kernels/blocked.cu.
- test_projected_pairs: the a135252-only harness's runtime_source is the
  historical receipt value (historical_runtime_source) in the receipt
  fixture and the two mocked run_case.main tests; runtime_source itself
  stays tested against the a135252 package (historical_package).
Harness files, pins, manifests and thresholds are unchanged.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/validation/run_refined_dfg.py

@@ -298,7 +298,8 @@ def verify_source(source, collision="SRT", observation_mode="last_base_step", je
         sys.path.insert(0, str(HERE))
         from source_provenance import checkout_provenance
 
-        paths = set(expected["sha256"])
+        # Harness files from the manifest; production files as this checkout lists them.
+        paths = {name for name in expected["sha256"] if not name.startswith("src/")}
         if observe_cv:
             paths.add("tests/validation/run_jet_circle_cv.py")
         paths.update(subprocess.check_output(
@@ -310,7 +311,8 @@ def verify_source(source, collision="SRT", observation_mode="last_base_step", je
                     for name in sorted(paths)},
         )
     for name, digest in expected["sha256"].items():
-        if hashlib.sha256((source / name).read_bytes()).hexdigest() != digest:
+        path = source / name
+        if not path.is_file() or hashlib.sha256(path.read_bytes()).hexdigest() != digest:
             raise RuntimeError("Source mismatch: " + name)
     return expected