fix(preamble): quoted tilde made Artifacts Sync and telemetry-finalize dead code in 49 skills

A tilde inside double quotes never expands, so the generated
`_BRAIN_SYNC_BIN="~/..."` assignments resolved to a literal ./~ path and
the Artifacts Sync + telemetry-finalize blocks silently no-op'd in every
skill that carried them (regression of #785). The preamble resolvers now
emit $HOME-based paths; all generated SKILL.md files regenerate identically
from the fixed templates, and a static tripwire fails the suite if a
quoted-tilde assignment ever reappears in generated output.

Fixes #1656, #1715.

Contributed by @jawadakram20 (PR #2333).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

test/no-quoted-tilde-assignments.test.ts

@@ -0,0 +1,51 @@
+import { describe, test, expect } from 'bun:test';
+import * as fs from 'fs';
+import * as path from 'path';
+
+// #1656 / #1715 (regression of #785): a tilde inside double quotes never
+// expands — `_BIN="~/.claude/..."` silently resolves to a literal ./~ path,
+// so the Artifacts Sync and telemetry-finalize blocks were dead code in every
+// generated skill. The resolvers now emit $HOME-based paths; this tripwire
+// fails the suite if a quoted-tilde assignment ever reappears in generated
+// output.
+
+const ROOT = path.resolve(import.meta.dir, '..');
+const QUOTED_TILDE_ASSIGN = /=\s*"~\//;
+
+function generatedDocs(): string[] {
+  const out: string[] = [];
+  for (const entry of fs.readdirSync(ROOT, { withFileTypes: true })) {
+    if (!entry.isDirectory() || entry.name.startsWith('.') || entry.name === 'node_modules') continue;
+    const skill = path.join(ROOT, entry.name, 'SKILL.md');
+    if (fs.existsSync(skill)) out.push(skill);
+    const sections = path.join(ROOT, entry.name, 'sections');
+    if (fs.existsSync(sections)) {
+      for (const f of fs.readdirSync(sections)) {
+        if (f.endsWith('.md')) out.push(path.join(sections, f));
+      }
+    }
+  }
+  const rootSkill = path.join(ROOT, 'SKILL.md');
+  if (fs.existsSync(rootSkill)) out.push(rootSkill);
+  return out;
+}
+
+describe('quoted-tilde assignments (#1656/#1715)', () => {
+  test('no generated doc assigns a double-quoted tilde path', () => {
+    const violations: string[] = [];
+    for (const file of generatedDocs()) {
+      const lines = fs.readFileSync(file, 'utf-8').split('\n');
+      for (let i = 0; i < lines.length; i++) {
+        if (QUOTED_TILDE_ASSIGN.test(lines[i])) {
+          violations.push(`${path.relative(ROOT, file)}:${i + 1}: ${lines[i].trim()}`);
+        }
+      }
+    }
+    expect(violations).toEqual([]);
+  });
+
+  test('detector self-check: the pre-fix shape is caught', () => {
+    expect(QUOTED_TILDE_ASSIGN.test('_BRAIN_SYNC_BIN="~/.claude/skills/gstack/bin/gstack-brain-sync"')).toBe(true);
+    expect(QUOTED_TILDE_ASSIGN.test('_BIN="$HOME/.claude/skills/gstack/bin/x"')).toBe(false);
+  });
+});