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>

hooks/gsd-graphify-update.sh

@@ -11,7 +11,7 @@
 # Gates (in fast-fail order — each shaves work off the common non-dispatch path):
 #   1. Stdin payload present and tool_name == "Bash"
 #   2. tool_input.command matches a HEAD-advancing git op (shell-direct or
-#      the exact `gsd-sdk query commit` command shape; the SDK command invokes
+#      the exact `gsd-tools query commit` command shape; the SDK command invokes
 #      git internally, so the literal "git commit" substring never appears —
 #      see #3653)
 #   3. $CI is unset/empty
@@ -49,10 +49,10 @@ COMMAND=$(printf '%s\n' "$TOOL_INFO" | sed -n '2p')
 
 [ "$TOOL_NAME" = "Bash" ] || exit 0
 
-# Gate 2 — HEAD-advancing git op (shell-direct or exact `gsd-sdk query commit`)
+# Gate 2 — HEAD-advancing git op (shell-direct or exact `gsd-tools query commit`)
 case "$COMMAND" in
   *"git commit"*|*"git merge"*|*"git pull"*|*"git rebase --continue"*|*"git cherry-pick"*) ;;
-  *"gsd-sdk query commit"|*"gsd-sdk query commit "*) ;;
+  *"gsd-tools query commit"|*"gsd-tools query commit "*) ;;
   *) exit 0 ;;
 esac