fix(observer): template literal regex escaping — \s/\d had wrong backslash count (v0.5.41)

Root cause: regex literals inside template literal (\...\) need exactly 2
backslashes (\\s, \\d) to produce \s, \d in the output. The v9 code had 4
backslashes (\\\\s) which produced literal \\s in the browser (matching
backslash+s instead of whitespace class). This broke:
- 'Running N commands' skip pattern (never matched)
- NOISE_CODE_RE (declare/import line filters)
- cleanLines() pre-strip word boundary \\b and split/join \\n
- cleanButtonText() whitespace strip \\s

The fix restores all regex-literal patterns to exactly 2 backslashes.
new RegExp() string patterns (like NOISE_RE) already used 4 backslashes
correctly (string→regex has one extra escaping layer).

Verified: node eval of generated code confirms /^Running\s*\d+\s*commands?$/i
correctly matches 'Running2 commands' and 'Running 4 commands'.

#task-619 #task-620

extension/package.json

@@ -2,7 +2,7 @@
   "name": "gravity-bridge",
   "displayName": "Gravity Bridge",
   "description": "Discord-based unified approval system for Antigravity AI interactions.",
-  "version": "0.5.40",
+  "version": "0.5.41",
   "publisher": "variet",
   "engines": {
     "vscode": "^1.100.0"