chore(memory): BDR-030 + LRN-042 + journal + TODO

Capitalize the install-self-sufficient / gstack-on-demand session:
- BDR-030: gstack skills activated on-demand per profile, OFF by default.
- LRN-042: npx skills add / setup resolve target relative to CWD — run
  from $HOME or artifacts land in the repo tree, unreachable by link.sh.
- journal 2026-06-23 line + TODO task block reconciled.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0169vjUD1sP9Nx4ZiCa8wvAw

.claude/memory/decisions.md

@@ -486,3 +486,15 @@ rules:
 - **Caveats**: the installer EDITS the submodule (goes dirty each run on a too-new OS) — invasive, but the user chose it over waiting upstream. `bun add playwright@latest` could pull a Playwright that breaks gstack's build → non-fatal (`./setup` fail warns, install continues). The local bump is reset by `git submodule update`. The `.bashrc` env can be wiped if the user restores a hand-managed `.bashrc` (theirs is managed — the first install's lines were already lost that way).
 - **Alternatives rejected**: `PLAYWRIGHT_HOST_PLATFORM_OVERRIDE` (fallback build HANGS at extraction — [[BLK-008]]); wait for gstack upstream Playwright bump (no ETA); leave browser unavailable (user wanted it); system chromium + executablePath (needs gstack code change).
 - **Reference**: `install-plugins.sh` `gstack_bump_playwright_if_unsupported()` + Step 9 sysctl-gated env, commit 3b8ffb1. Linked to [[LRN-040]], [[BLK-008]].
+
+---
+
+## BDR-030 — gstack skills activated ON-DEMAND per profile, not pre-installed; OFF by default stays
+
+- **Date**: 2026-06-23
+- **Status**: accepted
+- **Decision**: gstack stays OFF by default (no per-skill symlink in `skills/`, zero context cost) — but `profile.sh set <profile>` that LISTS a gstack skill activates it for that profile. `enable_skill gstack` gained a branch: skill not in `skills/` and not parked in `skills-disabled/` but present in the `skills-external/gstack/<name>` submodule → `ln -s` it into `skills/`. `disable_gstack_not_in()` parks it again when an unrelated profile is set. The gstack/bin + browse/dist infra those skills need is created independently by `link.sh`.
+- **Why**: user wanted `make install` self-sufficient AND `set full` (lists 35 gstack skills) to work without 35 `missing — try: bash link.sh` warnings, WITHOUT abandoning gstack's OFF-by-default context-cost policy ([[BDR-029]] install comment). On-demand-per-profile threads both: gstack invisible until a profile needs it, then auto-on for exactly that profile. Source of truth = the submodule (`gstack_skills()` already reads `skills-external/gstack/*/SKILL.md`), so activation needs no gstack `./setup` skill-registration (which this gstack version writes to the WRONG dir anyway — [[LRN-042]]).
+- **Caveats**: the symlink form (`skills/<name> -> skills-external/gstack/<name>`) differs from what gstack `./setup` would create (real dir + symlinked SKILL.md) — fine here because `./setup` never populates `skills/` in this layout, so no mixed-form collision. Browse RUNTIME still needs the built binary + sandbox env ([[BDR-029]]) — on-demand makes the skill DISCOVERABLE, not the browser functional on an unsupported OS. The old "try: bash link.sh" message was wrong (link.sh never creates gstack skills) → replaced with submodule-aware messages.
+- **Alternatives rejected**: full gstack integration (make `./setup` install into `skills/`) — user picked option 1, too invasive/version-fragile; leave `full` broken with honest 1-line warning — worse UX; pre-symlink all gstack at install — violates OFF-by-default context policy.
+- **Reference**: `lib/profile.sh` `GSTACK_SRC` + `enable_skill` gstack branch. Verified: `set full` → 0 missing, 35 on-demand; `minimal`↔`full` cycle re-parks/restores; git clean (gstack symlinks gitignored, [[LRN-025]]). Linked to [[LRN-042]], [[LRN-022]], [[BDR-018]] (gstack on/off verb).