[ljacomet]

Fixes #325

Why

A folder-scoped CLAUDE_CONFIG_DIR is only visible to a login shell started in that directory. Main never asked one: chat tabs spawned the bundled binary from Ness's own env, and every transcript, resume and hooks lookup hardcoded ~/.claude.

What changes

• New src/main/claude-env.ts. Runs the user's login shell in the worktree with a sentinel-wrapped env -0, caches the result per path, and re-probes on a spawn only when the entry is older than a minute so env edits made while Ness runs are picked up. Subdirectories resolve to their nearest cached ancestor. claudeConfigDirFor(cwd) falls back to Ness's env, then ~/.claude; an explicit claudeEnvVars.CLAUDE_CONFIG_DIR wins over the shell.
• Chat tabs start from the captured env instead of process.env, so they see what a terminal tab's zsh -ilc sees.
• Every ~/.claude/projects reader (--resume decision, transcripts, fork, context and cost trackers, cost roll-up) resolves through the same capture.
• Hooks are installed into settings.json of every Claude home a worktree maps to, and a newly seen home gets hooked when consent is already accepted.
• Hot path stays cold. A probe is a full shell startup, about a second on a heavy rc file. Sync readers only read the cache; the async entry points (startJsonClaudeSession, the agent:* request handlers, fork kickoff) await it, and worktrees are warmed on worktrees/listChanged. A chat start waiting on the probe absorbs a duplicate start and is cancelled by a kill, so closing a tab in that window leaves no orphan.
• Stale header in JsonClaudeManager (per-session temp CLAUDE_CONFIG_DIR) replaced with what the code does; CLAUDE.md gets a quirk entry.
• Probes are queued two at a time with a spawn's resolve jumping ahead
• A failed probe is retried rather than cached

Testing

• npm run typecheck, npx electron-vite build, npx vitest run all clean apart from three worktree-rename.integration tests that fail identically on main.
• New claude-env.test.ts covers parsing, cwd, timeout and missing-cwd handling, ancestor lookup, override precedence, in-flight dedup, and keeping the last good capture over a failed refresh.
• vitest.setup.ts clears CLAUDE_CONFIG_DIR so the suite does not depend on the developer's own Claude home.
• Manual: through the built module, a worktree below the folder-scoped export resolves to the alternate home, a subdirectory to the same one, and /tmp to ~/.claude.

Caveat

Sessions whose transcript was written to ~/.claude before the folder-scoped export existed still cannot resume, since the new home has no copy of them.