fix(#2791): GSD_WORKSTREAM env var respected by gsd-sdk query + gsd-tools bin alias (#2821)

* fix(#2791): GSD_WORKSTREAM env var respected by gsd-sdk query + gsd-tools bin alias

Two fixes for gsd-sdk binary issues:

**Issue 1 — Binary name collision:**
Both `get-shit-done-cc` and `@gsd-build/sdk` declare `bin: { "gsd-sdk": ... }`.
Added `"gsd-tools": "bin/gsd-sdk.js"` to `package.json` bin so users with the
collision can invoke `gsd-tools query <cmd>` as a conflict-free alternative.

**Issue 2 — Query registry not workstream-aware:**
`gsd-sdk query` commands ignored `GSD_WORKSTREAM` env var, always reading from
the root `.planning/` even when a workstream was active. `gsd-tools.cjs` reads
`GSD_WORKSTREAM` via `planningDir()`, so all ~35 `gsd-sdk query` call sites in
workflow files were broken in workstream-scoped projects.

Fix: added env var fallback in `sdk/src/cli.ts` — when `--ws` is not provided,
`GSD_WORKSTREAM` is used (with name validation; invalid values are silently
ignored, matching CJS behaviour).

Regression test: `tests/bug-2791-sdk-workstream-env.test.cjs`

Closes #2791

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* fix(#2791): address CodeRabbit — precedence test, invalid env fallback assertion, bash fence

---------

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

sdk/src/cli.ts

@@ -341,6 +341,17 @@ export async function main(argv: string[] = process.argv.slice(2)): Promise<void
     return;
   }
 
+  // Fall back to GSD_WORKSTREAM env var when --ws is not supplied (#2791).
+  // gsd-tools.cjs resolves the active workstream via this env var; parity
+  // means gsd-sdk query commands see the same .planning/ path as gsd-tools.
+  if (args.ws === undefined && process.env.GSD_WORKSTREAM) {
+    const envWs = process.env.GSD_WORKSTREAM;
+    if (validateWorkstreamName(envWs)) {
+      args = { ...args, ws: envWs };
+    }
+    // If the env var contains an invalid name, silently ignore it (same as CJS).
+  }
+
   // Multi-repo project-root resolution (issue #2623).
   //
   // When the user launches `gsd-sdk` from inside a `sub_repos`-listed child repo,