fix(docs): contract count 1331→1460 + wired Rust gate (PMAT-DRIFT-GATES-001)

[noahgift]

Fable rank-7 — a drift gate that never ran

scripts/check_readme_claims.sh is executable but wired into no workflow (grep -rn check_readme_claims .github/workflows → 0 hits). Only crate-count was enforced (a Rust test); the contract count rode entirely on the unwired script, so it drifted: README said 1331, canonical tree holds 1460.

The Fable note's "1766" was a dirty-worktree artifact — 306 uncommitted contracts/*.yaml on the local checkout that CI never sees. On origin/main: find contracts -name '*.yaml' == git ls-files == 1460. The RED/GREEN check caught my first attempt to write 1766.

Changes

• README: **1331**→**1460** + 1158→1460 (prose)
• CLAUDE.md: crates 80/70→82 (3×), contracts 1148/1134→1460 (2×)
• NEW readme_contract.rs::test_readme_contract_count_matches_workspace (FALSIFY-README-007) — rides the already-wired cargo test job; no ci.yml / branch-protection change

README says	test
1460	✓ suite 11/11 green
1331 / 1766	✗ panics README lacks **1460** provable contracts

Deferred

CLI-command count drifted 103→104 (apr --help); book-CLI-chapter parity (103) must reconcile with it — needs an apr build in the test job + a chapter check.

🤖 Generated with Claude Code

[noahgift]

Rebased onto `main` and corrected the count.

The pinned 1460 was already stale. The tree holds 1766 by the README's own documented command (`find contracts/ -name '*.yaml'`). The count has now moved four times — 1331 (README) → 1134/1148 (CLAUDE.md) → 1460 (this PR as written) → 1766 (actual) — which is exactly the argument for the gate this PR adds: FALSIFY-README-007 computes the number from the tree at test time, so it cannot be pinned wrong again.

Corrected in all four places: README.md:44, README.md:256, CLAUDE.md:5, CLAUDE.md:313.

Mutation-verified (RED on bug / GREEN on fix):

README 1766 -> cargo test -p aprender-core --test readme_contract : 11 passed
README 1460 -> FAILED: FALSIFY-README-007: README lacks `**1766** provable
               contracts` matching `find contracts/ -name '*.yaml'`

scripts/check_readme_claims.sh now reports PASS FALSIFY-README-002 contract_count: 1766.

---

Separate defect surfaced, not fixed here: that same script reports
FAIL FALSIFY-README-003 cli_command_count: README claims 103, apr --help lists 104.

It measures from HEAD source (cargo run -p apr-cli --bin apr -- --help), so 104 is authoritative — not a stale-binary artifact. It is wired into no workflow, so it does not block this PR. Fixing it also touches the Book CLI chapters | **103** | (parity with CLI) row, so it gets its own PR.