feat(plan-01): Phase 4a — make harness location-independent (facade-free capable)

Resolve every root by marker walk-up instead of a fixed depth that only lands on the
app via the .specify compat symlink, so the harness runs correctly when invoked by its
real packages/casan-harness path — proven by a full gate run via that path: 64/0/0.

- 95 scripts/tests: PROJECT_ROOT/ROOT "$SCRIPT_DIR/../.."-style computations -> $CASAN_APP_ROOT.
- 6 leaf scripts (infra-lab, context-validate, secrets-scan, path-guard, toolchain-verify,
  phase2-sourcegen) now source casan-paths + use CASAN_APP_ROOT.
- run-casan4: source casan-paths as a package sibling (facade-independent), PROJECT_ROOT=CASAN_APP_ROOT.
- 8 Python files: project_root()/REPO_ROOT/bundle_root walk UP for the .specify marker
  (control-plane-settings, loop_common, model-call, context-compress, test-integrity,
  bundle-integrity, traceability-matrix; generate-* fixed earlier).
- evidence-pack-build.py + traceability-matrix.py: domain refs -> apps/okr/domain
  (input/, corpus/redteam-vectors.jsonl, traceability-map.json).
- ci-harness-gate.sh: export CASAN_TESTS_DIR/CASAN_TEST_MANIFEST/CASAN_BUNDLE_ROOT so the
  integrity Python resolves via the harness root regardless of invocation path; ROOT=CASAN_APP_ROOT.
- Remove the domain compat symlinks from packages/casan-harness/security (redteam-corpus,
  redteam-vectors, benign-corpus) — packages now holds NO domain data.

Both invocation paths pass (compat facade still present): .specify/... and packages/...

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

AINative_OKR_CASAN5/packages/casan-harness/tests/phase-sec26-tests.sh

@@ -16,7 +16,7 @@ set -uo pipefail
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 source "$SCRIPT_DIR/../scripts/bash/casan-paths.sh"
-PROJECT_ROOT="$(cd "$SCRIPT_DIR/../.." && pwd)"
+PROJECT_ROOT="$CASAN_APP_ROOT"
 SCS="$CASAN_HARNESS_ROOT/scripts/bash/stored-content-scan.sh"
 WORK="$(mktemp -d)"
 trap 'rm -rf "$WORK"' EXIT