[eezzekl]

Summary

• Adds skill-sync import <skill-name>: a selective, single-skill import from the globally configured agent sources into the project-local ./.agents/skills/<skillID>/. This is distinct from mesh sync — it pulls one skill into the current project instead of reconciling every target.
• Introduces internal/importer, a reusable primitive (FindSkill, FindAllSkills, Resolve, CopySkill, DirHash) that delegates winner selection to the existing mesh resolver.
• Wires the flow into the TUI with two new views and two new states, including a [CONFLICT] marker for candidates the resolver cannot settle.

Design notes

Directory-level hashing. DirHash hashes a sorted manifest of every regular file in the skill directory (relative path + contents, filepath.ToSlash normalized for cross-platform determinism), not just SKILL.md. A skill whose sibling files changed is correctly seen as different.

Transactional copy. CopySkill writes everything into a .tmp staging directory first. On failure it removes .tmp and leaves the destination completely untouched; only on full success does it rotate the existing directory to .bak and rename .tmp into place. This avoids the window where a naive rename-then-write leaves a half-written destination.

Conflict handling. When two sources report the same version and the same mtime but different hashes, the import fails with ErrConflict and exit code 1 in both CLI and TUI. Interactive tie-breaking is deliberately out of scope for v1.

Changes

File	Change
internal/importer/manifest.go	DirHash — SHA-256 over the sorted file manifest; skips symlinks
internal/importer/importer.go	FindSkill, FindAllSkills (grouped by skill ID + resolved), Resolve, CopySkill, readMetadata
internal/importer/errors.go	ErrSkillNotFound, ErrConflict sentinels
internal/cli/import.go	NewImportCmd + runImport; uses the getWd package var for test injection
internal/cli/root.go	Registers the command and wires the FindSkillsForImport / RunImport callbacks
internal/models/skill.go	SkillMetadata gains Description for the TUI listing
internal/tui/import_source_view/	Agent source filter, built on shared_toggle, all sources checked by default
internal/tui/import_skill_view/	Single-select skill picker, [CONFLICT] prefix, description truncated at 60 runes
internal/tui/program.go	stateImportSource and stateImportSkill, plus the importSources field so BackMsg can recreate the source view
internal/tui/menu/model.go	"Import" item between Verify and Config
openspec/	SDD scaffolding and the full skill-import change record (proposal, spec, design, tasks)
.gitignore	Ignores local agent tool directories and test backup residue

Test plan

All run on feat/import_skills at c2cba25, and confirmed green in CI on ubuntu-latest and windows-latest:

• go build ./... — passes
• go vet ./... — passes
• gofmt -s -l . — clean (the first CI run caught unformatted files; fixed in c2cba25)
• go test ./... — passes, every package green

New coverage, all table-driven per project convention:

• internal/importer/manifest_test.go — determinism, order independence, content change, file addition, symlink skipping (Unix only, t.Skip on Windows)
• internal/importer/importer_test.go — find/resolve/copy paths including the transactional failure case where the destination must stay untouched
• internal/cli/import_test.go — 8 integration tests against real temp dirs: happy path, missing config, skill not found, wrong argument count (x2), conflict, idempotent re-import, and .bak backup creation
• internal/models/skill_test.go — description YAML round-trip
• TUI view tests for both new views, plus menu and program.go state transitions

Not applicable: shellcheck (no shell scripts touched).

Review size

~2,100 added lines, of which ~1,200 are tests — above the 400-line advisory budget in openspec/config.yaml, which declares chained_pr_strategy: single-pr-default. Suggested reading order: internal/importer/ first (the primitive and its invariants), then internal/cli/import.go, then the TUI wiring.

Known follow-ups

• A test in internal/tui writes skill-sync.yaml.bak into the package directory instead of a temp dir. This PR only gitignores the residue; the test should be fixed to use t.TempDir().
• sdd-archive for the skill-import change (merge delta specs, move the change folder to archived) is not included here.