chore(#191): retire the gsd-sdk shim — route everything at gsd-tools (#522)

* chore(#191): migrate gsd-sdk query call sites to gsd-tools query

Retiring the gsd-sdk shim. gsd-tools.cjs already accepts `query` as a
meta-prefix (gsd-tools query <command>), so this is a behavior-preserving 1:1
swap across the runtime reference prompts, the graphify hook's commit-detection
gate, and two bin/lib comment/message references.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* chore(#191): remove vestigial gsd-sdk shim code from installer + projection

The gsd-sdk shim was already not wired up (no gsd-sdk bin in package.json;
buildWindowsShimTriple had zero call sites). Remove the dead code:
- shell-command-projection.cjs: buildWindowsShimTriple + formatSdkPathDiagnostic
  (+ their now-unused PACKAGE_NAME import) and exports
- install.js: the re-export wrappers + imports, the #3406 stale-standalone-sdk
  detection (detectStaleStandaloneSdk/formatStaleStandaloneSdkWarning + its
  global-install call site), and the exports

Preserved (retained, not gsd-sdk): buildCodexHookWindowsShimIR (#3426) — only
its comments referenced the gsd-sdk pattern; reworded. Also kept the
homePathCoveredByRc 'reopen your shell' branch in maybeSuggestPathExport — its
logic is bin-dir-agnostic, only the message mentioned gsd-sdk; reworded to use
the actual bin dir.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* test(#191): update tests for retired gsd-sdk shim

- bug-3441/bug-3442: drop the formatSdkPathDiagnostic / buildWindowsShimTriple
  assertions (functions removed); retained PATH-action + drift-guard tests stay
- bug-505: remove the 'still exported' assertions for detectStaleStandaloneSdk /
  formatStaleStandaloneSdkWarning / the shim contract surface (#505 kept them;
  #191 removes them)
- graphify-auto-update: migrate the hook-dispatch inputs gsd-sdk query commit ->
  gsd-tools query commit to match the migrated commit hook

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* docs(#191): point active docs at gsd-tools query (gsd-sdk shim retired)

Update the user/agent-facing docs (AGENTS, COMMANDS, CONFIGURATION, USER-GUIDE,
ship-pr-body-sections) that presented gsd-sdk query as a current command to
gsd-tools query. Historical docs (ADRs, PRDs, release notes) left untouched.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* docs(#191): correct state.load vs state.json description for gsd-tools query

Adversarial-review (codex) finding: the migrated USER-GUIDE line claimed both
'gsd-tools query state.json' and 'state.load' resolve to the frontmatter-rebuild
handler. Verified they don't — state.load returns the CJS load shape
(config + state_raw + flags), state.json returns the frontmatter shape. Both are
available via gsd-tools query; corrected the text to say so.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* chore(#191): add changeset for gsd-sdk shim retirement

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

docs/USER-GUIDE.md

@@ -1095,11 +1095,11 @@ Each workspace gets:
 
 ## Troubleshooting
 
-### Programmatic CLI (`gsd-sdk query` vs `gsd-tools.cjs`)
+### Programmatic CLI (`gsd-tools query` vs `gsd-tools.cjs`)
 
-For automation and copy-paste from docs, prefer **`gsd-sdk query`** with a registered subcommand (see [CLI-TOOLS.md — SDK and programmatic access](CLI-TOOLS.md#sdk-and-programmatic-access) and [QUERY-HANDLERS.md](../sdk/src/query/QUERY-HANDLERS.md)). The legacy `node $HOME/.claude/get-shit-done/bin/gsd-tools.cjs` CLI remains supported for dual-mode operation.
+For automation and copy-paste from docs, prefer **`gsd-tools query`** with a registered subcommand (see [CLI-TOOLS.md — SDK and programmatic access](CLI-TOOLS.md#sdk-and-programmatic-access) and [QUERY-HANDLERS.md](../sdk/src/query/QUERY-HANDLERS.md)). The legacy `node $HOME/.claude/get-shit-done/bin/gsd-tools.cjs` CLI remains supported for dual-mode operation.
 
-**CLI-only (not in the query registry):** **graphify**, **from-gsd2** / **gsd2-import** — call `gsd-tools.cjs` (see [QUERY-HANDLERS.md](../sdk/src/query/QUERY-HANDLERS.md)). **Two different `state` JSON shapes in the legacy CLI:** `state json` (frontmatter rebuild) vs `state load` (`config` + `state_raw` + flags). **`gsd-sdk query` today:** both `state.json` and `state.load` resolve to the frontmatter-rebuild handler — use `node …/gsd-tools.cjs state load` when you need the CJS `state load` shape. See [CLI-TOOLS.md](CLI-TOOLS.md#sdk-and-programmatic-access) and QUERY-HANDLERS.
+**CLI-only (not in the query registry):** **graphify**, **from-gsd2** / **gsd2-import** — call `gsd-tools.cjs` (see [QUERY-HANDLERS.md](../sdk/src/query/QUERY-HANDLERS.md)). **Two distinct `state` JSON shapes, both available via `gsd-tools query`:** `state.json` (frontmatter rebuild) vs `state.load` (`config` + `state_raw` + flags) — they resolve to different handlers, so pick the one whose shape you need. The legacy `gsd-tools.cjs state json` / `state load` forms produce the same two shapes. See [CLI-TOOLS.md](CLI-TOOLS.md#sdk-and-programmatic-access) and QUERY-HANDLERS.
 
 ### STATE.md Out of Sync