feat(skills): normalize skill discovery contract across runtimes (#2261)

docs/skills/discovery-contract.md

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+# Skill Discovery Contract
+
+> Canonical rules for scanning, inventorying, and rendering GSD skills.
+
+## Root Categories
+
+### Project Roots
+
+Scan these roots relative to the project root:
+
+- `.claude/skills/`
+- `.agents/skills/`
+- `.cursor/skills/`
+- `.github/skills/`
+- `./.codex/skills/`
+
+These roots are used for project-specific skills and for the project `CLAUDE.md` skills section.
+
+### Managed Global Roots
+
+Scan these roots relative to the user home directory:
+
+- `~/.claude/skills/`
+- `~/.codex/skills/`
+
+These roots are used for managed runtime installs and inventory reporting.
+
+### Deprecated Import-Only Root
+
+- `~/.claude/get-shit-done/skills/`
+
+This root is kept for legacy migration only. Inventory code may report it, but new installs should not write here.
+
+### Legacy Claude Commands
+
+- `~/.claude/commands/gsd/`
+
+This is not a skills root. Discovery code only checks whether it exists so inventory can report legacy Claude installs.
+
+## Normalization Rules
+
+- Scan only subdirectories that contain `SKILL.md`.
+- Read `name` and `description` from YAML frontmatter.
+- Use the directory name when `name` is missing.
+- Extract trigger hints from body lines that match `TRIGGER when: ...`.
+- Treat `gsd-*` directories as installed framework skills.
+- Treat `~/.claude/get-shit-done/skills/` entries as deprecated/import-only.
+- Treat `~/.claude/commands/gsd/` as legacy command installation metadata, not skills.
+
+## Scanner Behavior
+
+### `sdk/src/query/skills.ts`
+
+- Returns a de-duplicated list of discovered skill names.
+- Scans project roots plus managed global roots.
+- Does not scan the deprecated import-only root.
+
+### `get-shit-done/bin/lib/profile-output.cjs`
+
+- Builds the project `CLAUDE.md` skills section.
+- Scans project roots only.
+- Skips `gsd-*` directories so the project section stays focused on user/project skills.
+- Adds `.codex/skills/` to the project discovery set.
+
+### `get-shit-done/bin/lib/init.cjs`
+
+- Generates the skill inventory object for `skill-manifest`.
+- Reports `skills`, `roots`, `installation`, and `counts`.
+- Marks `gsd_skills_installed` when any discovered skill name starts with `gsd-`.
+- Marks `legacy_claude_commands_installed` when `~/.claude/commands/gsd/` contains `.md` command files.
+
+## Inventory Shape
+
+`skill-manifest` returns a JSON object with:
+
+- `skills`: normalized skill entries
+- `roots`: the canonical roots that were checked
+- `installation`: summary booleans for installed GSD skills and legacy Claude commands
+- `counts`: small inventory counts for downstream consumers
+
+Each skill entry includes:
+
+- `name`
+- `description`
+- `triggers`
+- `path`
+- `file_path`
+- `root`
+- `scope`
+- `installed`
+- `deprecated`
+