refactor(public-safety): centralize compact identifier shapes

[karenchuu]

Summary

Centralizes the identical compact public-safe reference, compact token, and module-qualified surface regular expressions in loopx/public_safe_text.py. Reward Memory, Semantic Preference, Decision Context, and Material Lifecycle retain their existing field-level behavior and error messages while consuming the shared compiled patterns.

Also adds a focused ownership regression test that verifies the listed consumers share the owner objects (is, not ==) and no longer restate the literals.

Delivery brief

• Goal/source: remove demonstrated duplicated identifier/surface-shape decisions across the named capability contracts.
• Current gap: three shape rules were independently compiled in 12 modules, so a one-character edit in any one of them would silently drift the others.
• Observable result: each migrated consumer aliases the canonical compiled pattern; validation semantics remain unchanged.
• Owning boundary: loopx/public_safe_text.py owns syntax shapes only, while callers retain contract-specific field names, thresholds, policy and diagnostics.

Relationship to #5350 and #5296

This replaces #5350, which carried the same content from a different account; #5350 is closed with a pointer here.

Rebased onto a7e6b826a. Two files conflict on the way because #5296 landed between the original branch point and this base: decision_context/packets.py and material_lifecycle/_validation.py no longer carry _LOCAL_PATH_RE (that check now goes through find_public_safe_local_path). Resolution kept #5296's owner call and its explanatory comments verbatim, and removed only the duplicated _TOKEN_RE literal in favour of the shared import. Both files keep a net line delta of 0, which is what preserves the two project_registry_io census sites recorded for _validation.py.

Validation

• pytest -q tests/control_plane/test_compact_identifier_shape_owner.py — 3 passed.
• pytest -q tests/architecture --ignore=tests/architecture/test_semantic_production.py — 1009 passed / 0 failed (2m21s); tests/architecture/test_semantic_production.py separately — 34 passed.
• pytest -q tests/architecture/test_project_registry_io_census.py — 7 passed (needs the typescript dev dependency installed; run from a tree with node_modules).
• pytest -q tests/capabilities tests/test_decision_context_material.py plus the new guard — 1831 passed / 9 failed / 42 skipped (4m15s). All 9 failures are in tests/capabilities/test_repository_change_window.py, which spawns the loopx console script; they reproduce identically (9 failed / 8 passed) on an unmodified worktree at a7e6b826a under the same interpreter and PATH, so they are an environment artifact of this machine and not a regression from this change.
• examples/semantic-vocabulary-drift-smoke.py — ok. Measured counts are byte-identical between the unmodified base and this head (multi_value_twins=8/8, same_runtime_forks=11/11, conflicting_values=16/16, schema_version_same_runtime_forks=2/2), so no budget anchor moves: the three shapes were never registered as twins, and removing the duplicates does not by itself lower a budget.
• python -m ruff check on all 14 changed files — all checks passed; python -m mypy (no arguments, as CI runs it) — Success: no issues found in 19 source files; git diff --check — clean.
• loopx check --scan-path over public_safe_text.py, the four capability packages and the new guard — errors=0, public boundary scan clean: 77 files.
• loopx canary premerge with the 14 changed files listed explicitly — selected=10 executed=10 failures=0 advisory_failures=0.
• Disclosure: this run reused an already-installed local virtualenv interpreter and a node_modules symlink from another worktree (after diffing package.json dependencies and devDependencies field by field, identical) instead of a fresh uv sync --extra test, and pointed PYTHONPATH at this tree. The commands above are what actually ran, with PYTHONPATH and PATH (Node 22.23.2) set that way.

Scope

• Changed surfaces: shared public-safe shape owner; Reward Memory, Semantic Preference, Decision Context, and Material Lifecycle Python contract validation.
• No frontend, CLI, permission, persistence, default-off, or authority behavior changes.
• Future-facing refactor pass: applied; this removes duplicate shape authority without changing validation behavior.
• Not in scope: chat_action_store.py / chat_actions.py / goals/deletion_service.py each compile the same ^[A-Za-z0-9._:-]{1,200}$, and global_risks.py / global_todos.py / summary_all.py each restate the same SCHEMA_VERSION value. Those are separate owners with different contract lifetimes and are left for their own PRs rather than folded in here.