Add bounded definition and reference navigation for current source drafts

Preserve loaded draft bytes and model history, reject stale workspace and input events, and keep captured Escape under modal priority. Verified 181 focused Windows tests and strict desktop Clippy on exact inputs4; earlier full737 scope and component/native preparation evidence are archived separately. Native navigation acceptance remains pending.

harness/experiments/text-navigation-desktop-20260911/capture.py

@@ -0,0 +1,63 @@
+"""Preserve exact current source bytes before a gate and read them back after it."""
+import datetime
+import hashlib
+import json
+import pathlib
+import re
+import subprocess
+import sys
+import zipfile
+
+root = pathlib.Path(__file__).resolve().parents[2]
+evidence = pathlib.Path(__file__).resolve().parent
+mode, label = sys.argv[1:]
+assert re.fullmatch(r"inputs[0-9]+", label)
+
+def paths():
+    result = subprocess.run(["git", "ls-files", "-z", "--cached", "--others", "--exclude-standard", "--",
+        "crates", ".cargo", "Cargo.toml", "Cargo.lock", "docs", "examples", "harness/fixtures"],
+        cwd=root, check=True, capture_output=True)
+    return sorted(set(p.decode("utf-8") for p in result.stdout.split(b"\0") if p))
+
+def data(path):
+    target = (root / path).resolve()
+    assert target.is_relative_to(root) and target.is_file(), path
+    return target.read_bytes()
+
+def sha(raw):
+    return hashlib.sha256(raw).hexdigest()
+
+def write(path, value):
+    with path.open("x", encoding="utf-8", newline="\n") as out:
+        json.dump(value, out, indent=2, ensure_ascii=False)
+        out.write("\n")
+
+if mode == "capture":
+    entries = []
+    archive = evidence / (label + ".zip")
+    with zipfile.ZipFile(archive, "x", zipfile.ZIP_DEFLATED) as out:
+        for path in paths():
+            raw = data(path)
+            out.writestr(path, raw)
+            entries.append({"path": path, "bytes": len(raw), "sha256": sha(raw)})
+    result = {"atUtc": datetime.datetime.now(datetime.timezone.utc).isoformat(),
+        "head": subprocess.check_output(["git", "rev-parse", "HEAD"], cwd=root).decode().strip(),
+        "branch": subprocess.check_output(["git", "branch", "--show-current"], cwd=root).decode().strip(),
+        "scope": "Exact Windows gate source inputs; no compiler or native result implied.",
+        "archiveSha256": sha(archive.read_bytes()), "files": entries}
+    write(evidence / (label + ".json"), result)
+    print(json.dumps({"files": len(entries), "bytes": sum(e["bytes"] for e in entries), "archiveSha256": result["archiveSha256"]}))
+elif mode == "verify":
+    before = json.loads((evidence / (label + ".json")).read_text(encoding="utf-8"))
+    current = paths()
+    expected = [e["path"] for e in before["files"]]
+    changed = [e["path"] for e in before["files"] if sha(data(e["path"])) != e["sha256"]]
+    result = {"atUtc": datetime.datetime.now(datetime.timezone.utc).isoformat(),
+        "changed": changed, "added": sorted(set(current) - set(expected)),
+        "removed": sorted(set(expected) - set(current))}
+    result["passed"] = not any(result[k] for k in ("changed", "added", "removed"))
+    write(evidence / (label + "-readback.json"), result)
+    print(json.dumps(result))
+    sys.exit(0 if result["passed"] else 1)
+else:
+    raise ValueError(mode)