Add telemetry batch routing advisor

[ictechgy]

Summary

• add context-guard-cost route-advisor plus context-guard route-advisor dispatcher alias for local-only total-cost, batchability, and route-candidate advice
• combine caller-supplied workload JSON, provider feature declarations, usage telemetry, and shifted external/local cost sidecars without provider calls or queue runtime
• document conservative claim boundaries and provider-feature recheck requirements across root, kit, and packaged plugin docs
• add tests for shifted-cost accounting, invalid telemetry fallback, zero-cost tracking, tool-call shifted-cost warnings, provider-qualified model pricing, path-like model redaction, sanitized feature errors, and dispatcher help

Quad review

• Claude re-review: APPROVE_WITH_NITS; medium USD/KRW source-of-truth concern fixed
• Agy review/re-review: APPROVE, no critical/high/medium blockers
• Forge initial review: BLOCK on shifted-cost undercounting; fixed. Post-fix Forge re-review hung before final verdict; partial logs led to additional docs/path-redaction hardening
• Codex review/final v2: prior issues fixed; no remaining critical/high/medium issues

Validation

• python3 -m unittest tests.test_context_guard_kit -k cost_guard => 57 tests OK
• python3 -m py_compile context-guard-kit/cost_guard.py plugins/context-guard/bin/context-guard-cost context-guard-kit/context_guard_commands.py plugins/context-guard/lib/context_guard_commands.py
• python3 scripts/sync_plugin_copies.py --check
• git diff --check
• PYTHONDONTWRITEBYTECODE=1 python3 scripts/prepublish_check.py --skip-tests
• PYTHONDONTWRITEBYTECODE=1 python3 scripts/release_smoke.py --timeout 20
• PYTHONDONTWRITEBYTECODE=1 python3 scripts/prepublish_check.py => 691 tests OK in 247.419s