What changed

A Flow workspace git-ignores .claude/ so the runtime's worktrees and agent scratch never show up as untracked noise

This change delivers the following acceptance criteria:

• AC1: Given /flow:init provisions a workspace whose .gitignore does not already ignore .claude/, When init writes workspace config, Then .claude/ is git-ignored (a .gitignore is created or appended to) so the runtime worktrees and agent scratch are invisible to git, and any other existing .gitignore rules are preserved (append-safe, no clobber).
• AC2: Given a workspace whose .gitignore already contains a .claude/ ignore rule, When /flow:init runs, Then it does not duplicate the rule and leaves the rest of .gitignore unchanged (idempotent).

Why

As an operator initialising a Flow workspace in my own project, I want /flow:init to git-ignore .claude/ in my workspace, so that the Claude Code runtime's per-story worktrees (under .claude/worktrees/) and agent scratch do not appear as untracked noise in my git status.

How to check it yourself

Run the init-workspace tests: cd plugins/flow/mcp-server && vitest run src/tools/tests/init-workspace.test.ts. The three new tests cover: (1) .gitignore created with .claude/ rule when absent, (2) .claude/ appended without clobbering existing rules, (3) no duplication when rule already present.

Risk and blast radius

Risk tier: medium

The change is scoped to the files in the diff below. Review the diff to judge its actual blast radius — including any effect on shared state, data schemas, or authentication paths — before approving.

What is explicitly not covered: reviewer verification of this summary's accuracy is handled by a separate companion story.

Evidence

The pre-pull-request build-and-test gate passed before this pull request was opened. No pull request can be opened by the automated flow unless both pnpm build and pnpm test exit 0 in the developer's working directory.

Per-criterion covering checks:

• AC1 → plugins/flow/mcp-server/src/tools/__tests__/init-workspace.test.ts (automated test)
• AC2 → plugins/flow/mcp-server/src/tools/__tests__/init-workspace.test.ts (automated test)

Story: native:01KVS11W2GGH84XQCWH79GMBQZ
Spec: .flow/native-stories/01KVS11W2GGH84XQCWH79GMBQZ.md
ACs:

• AC1: Given /flow:init provisions a workspace whose .gitignore does not already ignore .claude/, When init writes workspace config, Then .claude/ is git-ignored (a .gitignore is created or appended to) so the runtime worktrees and agent scratch are invisible to git, and any other existing .gitignore rules are preserved (append-safe, no clobber).
• AC2: Given a workspace whose .gitignore already contains a .claude/ ignore rule, When /flow:init runs, Then it does not duplicate the rule and leaves the rest of .gitignore unchanged (idempotent).

feat(init): git-ignore .claude/ on workspace init (append-safe, idempotent)