fix(#1865): runtime launcher honors CLAUDE_CONFIG_DIR (#2024)

* fix(#1865): runtime launcher honors CLAUDE_CONFIG_DIR

The gsd_run preamble resolved the Claude global install only at
$HOME/.claude/gsd-core/bin/, but the installer honors CLAUDE_CONFIG_DIR —
so a global install redirected via CLAUDE_CONFIG_DIR was invisible to every
gsd_run call (every command failed with 'gsd-tools.cjs not found').

The Claude resolver arm now uses ${CLAUDE_CONFIG_DIR:-$HOME/.claude},
matching the installer + the other runtimes' ${VAR:-default} pattern.
Default $HOME/.claude behavior is unchanged.

- _runtime-launcher.snippet.sh: Claude arm honors CLAUDE_CONFIG_DIR.
- sync-runtime-launcher.cjs re-run: 95 workflows/agents re-synced.
- review.md / discuss-phase.md: trimmed to stay under their byte budgets.
- runtime-launcher-parity.test.cjs: (A) substring updated for the new form
  + explicit #1865 assertion that the snippet honors CLAUDE_CONFIG_DIR.
- goldens + size baselines recaptured.

Closes #1865

* docs(#1865): backfill changeset pr 2024

tests/runtime-launcher-parity.test.cjs

@@ -1622,13 +1622,21 @@ describe('bug-444: resolver finds repo-local .claude install', () => {
         `Found snippet content:\n${content.trim()}`,
     );
 
-    // Must still contain the $HOME/.claude fallback arm
-    const homeClaudeIdx = content.indexOf('$HOME/.claude/gsd-core/bin/');
+    // Must still contain the $HOME/.claude fallback arm (#1865: now carried as
+    // the ${CLAUDE_CONFIG_DIR:-$HOME/.claude} fallback, so match the stem).
+    const homeClaudeIdx = content.indexOf('$HOME/.claude');
     assert.ok(
       homeClaudeIdx !== -1,
       `Snippet must still contain the $HOME/.claude fallback arm.`,
     );
 
+    // #1865: the Claude arm must honor CLAUDE_CONFIG_DIR (the installer writes
+    // there when it is set), with $HOME/.claude as the fallback.
+    assert.ok(
+      content.includes('${CLAUDE_CONFIG_DIR:-$HOME/.claude}/gsd-core/bin/'),
+      `Snippet's Claude arm must honor CLAUDE_CONFIG_DIR via \${CLAUDE_CONFIG_DIR:-$HOME/.claude}.`,
+    );
+
     // Repo-local check must appear BEFORE $HOME/.claude check (local overrides global)
     assert.ok(
       localClaudeIdx < homeClaudeIdx,