chore: [SHELL-CORE] top10 scripts + CI wiring

[rfreel]

Motivation

• Implement the first tranche (Top 10) of the MECE Pareto Bash toolset so the canonical loop can run a single PATCH-ONLY iteration with deterministic contracts.
• Make the loop safe and CI-enforced by adding gate/invariant tooling and a stub model adapter so CI can validate script contracts and loop invariants.

Description

• Added executable Ralph scripts and helpers: scripts/ralph/step.sh, scripts/ralph/apply_patch.sh, scripts/ralph/slice.sh, scripts/ralph/summarize_log.sh, scripts/ralph/precommit_gate.sh, scripts/ralph/ci_gate.sh, scripts/ralph/invariants.sh, and scripts/ralph/diff_budget.sh and updated scripts/ralph/loop.sh, scripts/ralph/radius.sh, and scripts/ralph/llm_stub.sh to conform to the required contracts (strict mode, --help, --self-test, deterministic outputs, and exit codes).
• Wired CI to perform script contract checks and gates by updating .github/workflows/ci.yml to call each script with --help and --self-test, run scripts/ralph/invariants.sh and scripts/ralph/ci_gate.sh, and run pre-commit.
• Updated .pre-commit-config.yaml to include a fast invariants local hook and kept the radius enforcement hook; updated README.md and AGENTS.md to document the PATCH-ONLY pipeline and one-iteration flow.
• Updated project metadata to record the tranche: added SHELL-010 to prd.json and appended an entry to progress.txt indicating the top-10 tranche was added.

Testing

• No automated CI tests were executed in this change set locally; CI has been updated to run scripts/ralph/invariants.sh --self-test, scripts/ralph/invariants.sh, scripts/ralph/ci_gate.sh, and pre-commit run --all-files on PRs and pushes and will validate the script contract checks (--help/--self-test) as configured in .github/workflows/ci.yml.

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[chatgpt-codex-connector]

Use extended regex for conflict marker scan

When rg is unavailable, the fallback uses grep -n "^(<<<<<<<|=======|>>>>>>>)", but basic grep treats | literally, so it only matches a line containing the literal string <<<<<<<|=======|>>>>>>> rather than any real conflict marker. In minimal environments without ripgrep, merge conflicts will slip past invariants.sh and CI even though the gate claims to enforce them. Consider grep -E (or escaping \|) so the alternation works as intended.

Useful? React with 👍 / 👎.

[rfreel]

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