Fix 10 audit bugs: path prefix matching, verdict parsing, CORS, stale-task detection, phase mapping

Batch 1 (High severity):
- Bug 1: --audit cat3 now checks .automaton/tasks/ paths
- Bug 4: Verdict PASS/FAIL uses structured ## Status: line parsing
- Bug 5: register-guards.sh checks .json/.jsonc, writes plugin key, strips comments
- Bug 7: --can-edit/--scope-check path prefix uses os.sep boundary

Batch 2 (Medium/Low severity):
- Bug 2: migrate-project.sh find command parentheses for -prune binding
- Bug 3: vram_detect model prefix matching with known-suffix whitelist
- Bug 6: dashboard reads .state file before artifact heuristic fallback
- Bug 8: removed wildcard CORS, added security headers (nosniff, DENY)
- Bug 9: stale-task detection uses .state.lastedit instead of .state mtime
- Bug 10: TEST_PLAN.md maps to test_design (was implement)

249 tests pass (up from 235). All 10 tasks driven through full workflow to completion.

tasks/fix-can-edit-path-prefix/SPEC.md

@@ -0,0 +1,30 @@
+# Spec: fix-can-edit-path-prefix
+
+## Problem
+`--can-edit` and `--scope-check` in `scripts/status.py` use `str(file_path).startswith(proj_str)` to verify a file is within the project directory. String `startswith` matches sibling directories: `/home/user/project-evil/file.py` matches prefix `/home/user/project`. This allows editing files outside the project boundary.
+
+Affected locations:
+- `scripts/status.py:951` (`--can-edit --project --file`)
+- `scripts/status.py:1004` (`--can-edit --task --file`, framework case)
+- `scripts/status.py:1010` (`--can-edit --task --file`, regular project case)
+- `scripts/status.py:1047` (`--scope-check`)
+- `scripts/status.py:1052` (`--scope-check`, framework check)
+
+## Fix
+Append a trailing path separator to the prefix before comparison:
+```python
+str(file_path).startswith(proj_str + os.sep)
+```
+Or use `Path.relative_to()` which correctly resolves path boundaries:
+```python
+try:
+    file_path.relative_to(project_dir.resolve())
+except ValueError:
+    # out of scope
+```
+
+## Acceptance Criteria
+- A file in `/home/user/project-evil/` is correctly rejected as out-of-scope when project is `/home/user/project`
+- A file in `/home/user/project/subdir/` is correctly accepted as in-scope
+- Both framework and regular project cases work
+- Add a test in `tests/test_status.py` covering the sibling-directory edge case