feat(plan-01): Phase 0.5 — path indirection via casan-paths.sh (no file moves)

Task 1.2: introduce a single path resolver so no harness script hardcodes
`.specify/...` scattered across the tree. casan-paths.sh resolves four roots
(HARNESS/STATE/GOVERNANCE/APP) by marker-based walk-up from its own location —
never `git rev-parse` (git root is the repo PARENT here, not the app dir).

- 101 bash scripts/tests: 238 hardcoded `$PROJECT_ROOT/.specify/...` refs rewritten
  to CASAN_HARNESS_ROOT (code) / CASAN_STATE_ROOT (logs,state) / CASAN_GOVERNANCE_ROOT.
  Sandbox test vars ($WORK/$TP/$FP/$T1_WORK) left untouched.
- Roots are NOT exported: each script/subprocess self-resolves from its own tree,
  matching the original per-script semantics and preserving hermetic sandbox isolation
  (node casan-step.mjs, copied telemetry/rollback scripts must not inherit real roots).
- Sandbox tests that copy a harness script now also copy casan-paths.sh (its new
  sibling dependency): adversarial (verify-audit-chain/verify-tool-audit/rollback) +
  track-a (security-check/telemetry-integrity).
- control-plane-settings.json reclassified as STATE (untracked runtime store).

Roots all still resolve to `.specify` in this monolithic layout, so behavior is
unchanged. Full gate: PASS=64 FAIL=0 SKIP=3 (adversarial 44/0, track-a 25/0).

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

AINative_OKR_CASAN5/.specify/scripts/bash/sign-audit-head.sh

@@ -21,13 +21,14 @@ set -euo pipefail
 #   VAULT_TOKEN  — token with transit/sign/casan-audit-key capability
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+source "$SCRIPT_DIR/casan-paths.sh"
 PROJECT_ROOT="$(cd "$SCRIPT_DIR/../../.." && pwd)"
 
-AUDIT_LOG="${1:-$PROJECT_ROOT/.specify/logs/audit/audit.jsonl}"
+AUDIT_LOG="${1:-$CASAN_STATE_ROOT/logs/audit/audit.jsonl}"
 AUDIT_DIR="$(dirname "$AUDIT_LOG")"
 HEAD_FILE="$AUDIT_DIR/audit-head.txt"
 HEAD_SIG="$AUDIT_DIR/audit-head.sig"
-AUDIT_PUB="$PROJECT_ROOT/.specify/level5/central-governance/audit-public.pem"
+AUDIT_PUB="$CASAN_GOVERNANCE_ROOT/audit-public.pem"
 
 if [[ ! -f "$AUDIT_LOG" ]]; then
   echo "SIGN_AUDIT_HEAD_SKIP audit.jsonl not found" >&2
@@ -102,7 +103,7 @@ PY
   fi
 else
   # Fallback — local key (dev environment without Vault)
-  AUDIT_PRIV="$PROJECT_ROOT/.specify/level5/central-governance/audit-private.pem"
+  AUDIT_PRIV="$CASAN_GOVERNANCE_ROOT/audit-private.pem"
   if [[ ! -f "$AUDIT_PRIV" ]]; then
     echo "SIGN_AUDIT_HEAD_SKIP no private key and VAULT_ADDR not set — verify will show anchor=unsigned" >&2
     exit 0