Python L1 static structural gate (pyright/mypy) for phase1/nat_semiring

[briansrls]

Summary

Worksheet A (PY-L1-STATIC-STRUCTURAL) for the Python release-minimum lane: land shared TargetStaticAnalysisInvocation / TargetStaticAnalysisVerdict carriers, pyright/mypy extdeps profiles, substrate claim rows, and a host gate chained from v4-phase1-nat-semiring-rung-gate.sh after R2-python-compile PASS.

Complements #4167 (L1 runtime exec + L2 harness), already on main. Static checks are advisory by default (SKIP when pyright/mypy absent); V4_PHASE1_NAT_SEMIRING_PYTHON_STATIC_STRICT=1 fail-closes on FAIL without coupling to parent STRICT.

Test plan

• cargo test -p v3-compiler v4_nat_semiring_rung_l1_python_static — claim DAG tokenize/parse
• CI: phase1 rung gate (pyright/mypy expected SKIP on runners without tools unless installed)

Worker attestation

• Title describes the change (not the session id or branch).
• PR body summarises what and why.
• Tests run: cargo test -p v3-compiler v4_nat_semiring_rung_l1_python_static — pass
• Closes work item: follow-on to Python L1/L2 typed runtime fixture execution implementation #4167 / manager dispatch (no Closes #N yet)
• No surprise commits; branch rebased on current main (post-Python L1/L2 typed runtime fixture execution implementation #4167).
• No secrets / credentials / large binaries staged.

[briansrls]

Closing per Python RCA Manager (witty-ram-95): overlaps active #4158 (Python static structural lane). #4167 runtime work is merged on main; this branch duplicated Worksheet A substrate that #4158 owns. Session crisp-crab-696 returns to idle unless explicitly re-tasked.

[briansrls]

Feedback triage (crisp-crab-696)

The dashboard item is this PR’s close comment (2026-06-01T12:40:40Z), not an external review finding. There are no REQUEST_CHANGES reviews, no inline review threads, and no api-review APPROVE/RC artifacts on this PR.

Action: None on code. Per Python RCA Manager (witty-ram-95, msg_3f0f231c): #4187 stays closed — Worksheet A static substrate overlaps active #4158; #4167 runtime is already on main. This session will not push further commits to this branch while #4158 is the authorized static lane.

CI note: The post-ready fmt failure on d027588 is acknowledged but out of scope for merge here (PR closed, not operator-authorized). Any fmt/static fixes belong on #4158 or a future explicitly re-tasked branch.

Merge readiness: N/A — state=CLOSED. Not pursuing ≥2 APPROVE / CLEAN / green CI on this PR.

— sent from crisp-crab-696