Improve read and grep long-line output

[konard]

Fixes #230

Summary

• Add shared JavaScript and Rust column-window formatting for long text output, including balanced first/last windows, explicit column windows, and match-focused windows.
• Update read to summarize long files with first/last line ranges by default and support columnOffset / columnLimit for selected lines.
• Update grep output to keep long matching lines bounded while preserving the matching segment with omitted-column markers.
• Add docs/case-studies/issue-230 with raw GitHub artifacts, online/library research, extracted requirements, alternatives, and verification notes.

Reproduction and Coverage

The regression tests create long files and long single-line fixtures that reproduce the issue behavior:

• default read now returns first and last line ranges with ... [omitted lines X..Y] ...;
• default read on one long line returns first columns, omitted-column range, and last columns;
• explicit columnOffset / columnLimit returns the requested column window;
• grep on a long line containing ivu-modal-header{cursor:move} returns the match-focused snippet instead of hiding or dumping the whole line.

Verification

cd js
bun test ./tests/tool_read.js ./tests/tool_grep.js
npm run check
npm test

cd rust
cargo fmt --check
cargo test --test tool_read --test tool_grep
cargo test

Observed locally: JS focused tests passed, JS check passed, full JS suite passed with 609 pass / 4 todo / 0 fail, Rust focused tests passed, and full Rust suite passed.

[konard]

Working session summary

Implemented issue #230 and updated PR #278: #278

Changes made:

• Added column-windowed read output in JS/Rust, including columnOffset and columnLimit.
• Updated default read output to show whole-file overviews and balanced long-line snippets.
• Updated grep/search output to show focused match snippets instead of dumping long lines.
• Added regression tests for read/search long-line behavior.
• Added the requested case study under docs/case-studies/issue-230.
• Added the required JS changeset after CI reported No changeset found.

Verification:

• Local: cd js && bun test ./tests/tool_read.js ./tests/tool_grep.js
• Local: cd rust && cargo test --test tool_read --test tool_grep
• Local: cd js && npm run check
• Local: full npm test, cargo fmt --check, and cargo test passed earlier.
• Remote CI on head 5ad3929: JS CI/CD and Rust CI/CD both passed.
• PR is ready for review, merge state is clean, and local git status is clean.

CI investigation logs were preserved outside the repo at ../ci-logs-issue-230.

Research sources used: ripgrep manpage, grep-printer JSON docs, ripgrep guide, and ripgrep issue #1451.

---

This summary was automatically extracted from the AI working session output.

[konard]

🤖 Solution Draft Log

This log file contains the complete execution trace of the AI solution draft process.

💰 Cost estimation:

• Model: GPT-5.5
• Provider: OpenAI
• Public pricing estimate: $14.694795

📊 Context and tokens usage:

• 407.6K / 200K (204%) input tokens, 54.1K / 128K (42%) output tokens

Total: (407.6K + 8.2M cached) input tokens, 54.1K output tokens, $14.694795 cost

🤖 Models used:

• Tool: OpenAI Codex
• Requested: gpt-5.5
• Thinking level: max (~31999 tokens)
• Model: GPT-5.5 (gpt-5.5)

📎 Log file uploaded as Gist (6703KB)

• View complete solution draft log

---

Now working session is ended, feel free to review and add any feedback on the solution draft.

[konard]

✅ Ready to merge

This pull request is now ready to be merged:

• All CI checks have passed
• No merge conflicts
• No pending changes

---

Monitored by hive-mind with --auto-restart-until-mergeable flag