Add stage1 Option and Result outcome helpers

[jmcte]

Summary

• Add std/outcome.ax with generic Option<T> and Result<T, E> helper predicates.
• Add fallback unwrap helpers that avoid introducing panic-based unwrap behavior.
• Add stage1/examples/stdlib_outcome and docs for the bounded helper surface.

Governing Issue

Closes #407

Validation

• cargo run --manifest-path stage1/Cargo.toml -p axiomc -- test stage1/examples/stdlib_outcome --json
• cargo fmt --manifest-path stage1/Cargo.toml
• git diff --check
• Required PR checks are expected to satisfy CI Gate
• Skipped checks are explained below

Bootstrap Governance

• Changes are scoped to the linked issue
• Contributor or PR guidance changes are reflected in docs where applicable
• No real secrets, runtime auth, or machine-local env files are committed

Notes

• Skipped broader stage1 gates to keep this small stdlib-only issue slice cheap; focused generated-native example coverage passed.

[athena-omt]

No blocking findings in the visible diff. The new std/outcome.ax helpers are scoped to pure Axiom match wrappers over the existing Option<T> and Result<T, E> forms, and the example/docs cover the intended bounded helper surface without adding host runtime or panic behavior.

I am leaving this as a comment rather than approval because the PR is currently reported dirty / non-mergeable, so the final merged diff still needs to be re-established against main. I also could not run local read-only checks from the required worktree because the command sandbox failed before starting commands with bwrap: Failed to make / slave: Permission denied.

Suggested non-blocking follow-up: after rebasing/merging main, consider extending stdlib_outcome to print the false predicate branches too (option_is_some(None), option_is_none(Some), result_is_ok(Err), result_is_err(Ok)) so every helper branch is represented explicitly.

[pheidon]

Pheidon sweep review: approved. I inspected the Option/Result outcome helper stdlib additions and example. The helpers are added to the synthetic stdlib surface with docs and a deterministic stdlib_outcome example covering is_some/is_none/is_ok/is_err-style usage. Validation: git diff --check origin/main...HEAD; cargo run --manifest-path stage1/Cargo.toml -p axiomc -- test stage1/examples/stdlib_outcome --json. No blocker found.