fix(observer/bridge): PROMPT_ONLY_RE — regex escaping + ellipsis prefix handling (v0.5.45) #task-619

Observer: \\\\s (4-backslash) → \\s (2-backslash) in template literal regex
  - Per known-issues rule: regex literals need 2-backslash for \s, \d etc.
  - Old: literal \\s matched, new: whitespace class matched correctly

http-bridge: /^[\s\\\/]*[\w_.-]+\s*[>»$#]\s*$/ → /^.*[>»$#]\s*$/
  - Old pattern failed on ellipsis '…' prefix (U+2026 not in charset)
  - Terminal prompt '…\\gravity_control >' was passing through as cmd
  - New pattern: any text ending with prompt marker is skipped

extension/package.json

@@ -2,7 +2,7 @@
   "name": "gravity-bridge",
   "displayName": "Gravity Bridge",
   "description": "Discord-based unified approval system for Antigravity AI interactions.",
-  "version": "0.5.44",
+  "version": "0.5.45",
   "publisher": "variet",
   "engines": {
     "vscode": "^1.100.0"