Add the public Programmable v4 Builder beta

[0xprogrammable]

Outcome

Adds the GitHub-only Programmable v4 Builder beta as a portable Agent Skill, deterministic checker, closed six-file application format, trusted-base intake validator, Codex and Claude plugin distributions, documentation, and maintenance workflows.

The intake status remains prelaunch in this pull request. No public application can pass until the bootstrap is merged, post-merge checks pass, branch protection requires all builder gates, and a separate reviewed status pull request changes the trusted state to open.

Scope

• 254 allowlisted public files: 246 new and 8 changed.
• Existing contracts, tests, models, deployments, release evidence, specs, security workflow, and artwork are unchanged.
• No internal plans, handoff state, private repository reference, local path, credential, wallet flow, deployment, or provider integration is included.
• Unknown mechanics enter architecture discussion; unfamiliarity alone is never a security rejection.
• A merged application is a public review record, not an audit, safety claim, model acceptance, deployment, provider support, or Uniswap endorsement.

Evidence

• public-port file closure: 254 expected, 254 present, zero byte mismatches, zero extra paths;
• canonical skill: green, 495-line portable entrypoint;
• trusted intake: 201 passed, one expected macOS/Linux-only platform skip locally;
• installed skill verifier: green;
• plugin generator and packaging: 10 of 10;
• eval structure: 7 of 7;
• documentation tests and full repository-relative link closure: green;
• model registry, release evidence, Foundry formatting, and actionlint: green;
• final private Linux maintenance, Foundry, Security, and trusted post-merge runs: green;
• independent breadth audit: 320 of 320 targeted cases;
• independent adversarial audit: no P0 or P1 finding; the one P2 race observation was fixed and regression-tested.

This is the bootstrap PR only. Public branch protection, external nipmod canary, exact pinned installation proof, and the versioned builder release remain mandatory before announcing the beta as open.