v0.1.1: require explicit repo selection + safe, bounded tool responses

[JonZavialov]

Motivation

• Prevent Segmint from scanning arbitrary filesystem when launched outside a git repo and give clients an explicit, deterministic way to pick the repository to operate on.
• Make tool outputs safe for large repos/clients by bounding returned arrays and providing deterministic truncation metadata.
• Improve first-run UX and cross-client portability by documenting explicit repo selection and adding minimal helpers to resolve repo roots.

Description

• Added two new Tier-1 tools: set_repo_root { path } which resolves a path to the git toplevel via git -C <path> rev-parse --show-toplevel and stores that repo root in server memory, and get_repo_root which returns the currently active repo root. (src/server.ts, src/exec-git.ts).
• Enforced repo-safety across all git-backed tools by requiring an active repo root before executing git commands and returning a structured error { isError: true, code: "SEGMINT_NO_REPO", message: "..." } when none is set; server still allows a safe startup fallback only if process cwd is already inside a repo (no wild scanning). (src/server.ts, gating added to all tools).
• Propagated explicit cwd/repo root into git helpers and read-only modules: execGit/tryExecGit accept cwd, added resolveGitRoot/tryResolveGitRoot, and history, show, diff, blame, changes pipelines accept cwd and use it consistently. (src/exec-git.ts, src/history.ts, src/show.ts, src/diff.ts, src/blame.ts, src/changes.ts).
• Added deterministic response-size safety via src/limits.ts with truncateArray and capChanges, and surfaced truncated: boolean + omitted_count: number in affected tool outputs (files, changes, hunks, blame lines) with deterministic truncation at 200 entries. Tools now include repo_root where applicable. (src/limits.ts, updated src/server.ts outputs).
• Added tests to prove the fix and maintain coverage: E2E regression for non-git startup + explicit set_repo_root flow, updated E2E tool listing, unit tests for truncation helpers and set_repo_root error handling, and an integration test for fresh repo HEAD edge case. (tests/e2e/repo-selection-safety.test.ts, updated tests/e2e/mcp-server.test.ts, tests/unit/limits.test.ts, tests/unit/server-repo-root.test.ts, tests/integration/status-empty-repo.test.ts).
• Documentation and contract updates: README and CLAUDE.md updated with install/run, JSON-RPC examples for set_repo_root/get_repo_root, first-run verification steps, Claude Desktop example (cwd optional), and explicit anti-drift guidance; bumped package to 0.1.1.

Testing

• Built the project with npm run build; successful.
• Ran the E2E suite with npm run test:e2e; all E2E tests passed.
• Ran full coverage with npm run test:coverage; test suite and coverage thresholds passed (build, E2E, integration and unit suites green and global branch coverage >= 95%).
• New and updated tests exercised: repo_status, list_changes, log, show_commit, diff_between_refs, blame, group_changes against a configured repo root; SEGMINT_NO_REPO behavior when started outside a git repo; truncation helper behavior and fresh-repo HEAD edge case.

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Codex Task