Support $CLAUDE_CONFIG_DIR for custom config paths

[zehua]

Problem

Claude Code supports $CLAUDE_CONFIG_DIR to override the default ~/.claude directory. However, gstack hardcodes ~/.claude/skills/gstack throughout the codebase (480 occurrences across 50 files). When a user runs Claude Code with a custom $CLAUDE_CONFIG_DIR, gstack silently references the default ~/.claude directory instead — reading the wrong memories, settings, and project config, and writing state to the wrong location.

Scope of affected files

Source-of-truth files (7 — must change)

File	Role
scripts/gen-skill-docs.ts	Defines skillRoot, binDir, browseDir on lines 42-45; embeds paths into all generated preamble/postamble templates
setup	Install script — creates symlinks in ~/.claude/skills/, rewrites paths for kiro/codex
scripts/skill-check.ts	Validates generated output contains correct host paths
browse/src/find-browse.ts	Binary discovery — searches ~/.claude/skills/gstack/browse/dist/browse
bin/gstack-global-discover.ts	Session discovery across ~/.claude/projects
bin/dev-setup	Creates .claude/skills/gstack dev symlink
bin/dev-teardown	Cleans up dev symlinks

Template files with their own hardcoded paths (~17 .tmpl files)

Several templates (notably gstack-upgrade/SKILL.md.tmpl with 19 refs, codex/SKILL.md.tmpl with 5, autoplan/SKILL.md.tmpl with 7) contain literal ~/.claude/skills/gstack in bash blocks beyond what the generator injects. These need fixing too.

Auto-fixed (no direct changes needed)

28 generated SKILL.md files — regenerated from templates when sources are fixed.

Also need updates

• 6 test files (verify path correctness in generated output)
• 8 documentation files (CLAUDE.md, ARCHITECTURE.md, etc.)

Proposed fix

Replace hardcoded ~/.claude with ${CLAUDE_CONFIG_DIR:-$HOME/.claude} at each layer:

1. gen-skill-docs.ts — change skillRoot, localSkillRoot, binDir, browseDir to use the dynamic pattern
2. setup — resolve install target via ${CLAUDE_CONFIG_DIR:-$HOME/.claude}
3. find-browse.ts — check $CLAUDE_CONFIG_DIR when searching for the browse binary
4. bin/dev-setup, bin/dev-teardown — same pattern
5. .tmpl files — replace literal ~/.claude/skills/gstack with the dynamic pattern in bash blocks
6. Regenerate all SKILL.md files

Relation to #289

Issue #289 (host integration contract RFC) proposes a broader abstraction for multi-host support. $CLAUDE_CONFIG_DIR support is a concrete, narrower fix that can land independently — it fixes a real bug for Claude Code users today without waiting for the full host adapter architecture. The fix naturally aligns with #289's direction since it makes path resolution dynamic rather than hardcoded.

Impact

Users running Claude Code with a custom $CLAUDE_CONFIG_DIR will have gstack silently reference the default ~/.claude directory. This means gstack reads the wrong memories, settings, and project config — and writes state (sessions, analytics, skill data) to the wrong location. No error or warning is shown.

[loocor]

Thanks for writing this up so concretely. I now have PR #364 open as the phase-1 install/runtime tranche of RFC #289:
#364

That PR does not add $CLAUDE_CONFIG_DIR support yet, but it does pull host layouts, discovery roots, and runtime roots into a single contract (scripts/host-registry.ts) instead of leaving them scattered across setup/templates/checks.

So to me this issue now looks like a strong, narrow follow-up on top of that contract: config-root resolution should become part of the host path model rather than another repo-wide literal-path cleanup.

[zehua]

@loocor let's figure out if the proposed fix in #351 could be merged first or be done on top of #364