v1.3.0

Release-tooling and CI hardening. Adds the /sd:release command (10th), a single-command repo invariant validator with a Windows + Ubuntu CI matrix, an uninstaller, and a batch of command/agent refinements.

Added

• /sd:release command (10th command) - generates release notes from completed specs: collects every spec in done status (feature / bug / refactor / perf; RCA excluded), groups them into Keep-a-Changelog sections (FEAT -> Added, BUG -> Fixed, REF/PERF -> Changed) under an inferred SemVer heading (any feature -> minor bump, else patch; major never auto-inferred), then transitions each done -> archived. One hard gate previews the notes and the archive plan before any write; --dry-run stops before writing. Pure file ops, no subagent (mirrors /sd:spec). Gives the done (merged, unshipped) vs archived (shipped) states a concrete meaning.
• scripts/validate.ps1 + scripts/validate.sh - one command that runs every documented engine invariant: pure-ASCII scan of *.ps1, bash -n on *.sh, hook-pair parity, agent model: alias-only check, install-target file counts (real install to a temp base), and a non-empty [Unreleased] CHANGELOG gate. Exit 1 on any failure.
• .github/workflows/ci.yml - runs validate on push/PR across a Windows + Ubuntu matrix, plus an install -> uninstall round-trip per the CLAUDE.md sandbox recipe.
• install/uninstall.ps1 + install/uninstall.sh - removes the five <base>/<area>/sd/ directories with dry-run preview, confirmation prompt (-Force/--force to skip), and per-project cleanup reminders (.claude/settings.json hook wiring, .claude/.hookstate/).

Changed

• scripts/validate.{ps1,sh} Check 6 now treats an empty [Unreleased] section as passing when the section immediately below it is a dated [x.y.z] - <date> release heading (the freshly cut version), so a clean post-release CHANGELOG no longer fails CI. A non-release-state empty [Unreleased] still fails, preserving the "every PR adds a changelog line" invariant.
• /sd:perf Gate 6 now structurally refuses a no-measurable-gain "keep" instead of merely warning about it in prose. The gate branches on the noise check: a measurable improvement still offers keep / revert, but a within-noise result defaults to revert and allows keep only as an explicit logged constitution exception (decision kept (exception) + a reason recorded to 05-retro.md). With no reason supplied, the change is reverted.
• docs/architecture.md gains two reference sections: a "Command -> agent routing" tree showing the subagent fan-out per command (and the three file-ops commands that invoke none), and an "Artifact ownership" table mapping each .specs/<ID>/ file to its producing phase/agent and downstream readers. Consolidates routing/ownership that previously lived only in scattered command files.
• /sd:setup Q1 and the sd-spec-architect ticket protocol now state explicitly that automatic ticket-context fetch is JIRA-only: GitHub Issues and Linear are still recorded as the project tracker (for prompt-hook ID recognition), but their ticket content is not auto-fetched - paste it into the prompt instead. The ticket snapshot protocol is documented as JIRA-specific. Closes the silent degradation where non-JIRA projects got no ticket fetch and no explanation.

Fixed

• /sd:spec status now spells out the illegal-transition refusal instead of the vague "REFUSED with explanation": it prints the current state, the requested state, the valid next state(s) from the state machine, and the shortest legal path to the requested state when reachable (e.g. draft -> done is rejected with the hint draft -> approved -> in-progress -> done). No file is mutated on refusal.
• /sd:bug Phase 3 no longer assumes a confirmed root cause always arrives. The investigation loop previously said "Continue until one is CONFIRMED" with no exit, so a bug whose every hypothesis is rejected/inconclusive had no defined stopping point. Added Gate 3a (hypothesis tree exhausted): the loop now terminates on a CONFIRMED hypothesis OR an exhausted tree, and the exhausted case STOPs and asks the user to re-enumerate (with new evidence), add observability, or abort as "root cause not found" - never guessing a fix from an unconfirmed tree.
• install/install.sh marked executable (mode 100755, matching uninstall.sh); it was 100644, so the documented ./install/install.sh invocation failed with "Permission denied" on a fresh Linux checkout. Surfaced by the new CI round-trip.
• install/README.md: total file count corrected (21 -> 32), skills/sd/ added to the layout tree, install table, and manual uninstall commands (skills were missed since 1.1.0), and the -Prefix/--prefix option documented.