docs: remove references to the source app and recording

Prepare for open-sourcing: scrub the prior-art attribution from the spec,
agent guide, and code comments so the project documents its own behavior.

- Reword RULES_FEATURE_SPEC.md to describe OpenAppLock's rules feature
  directly (drop the screen-recording source line and "as observed"/
  "not demoed"/"as shown" framing)
- Replace "the reference app/UI/style/defaults" comments and test names
  with direct descriptions of the behavior
- No behavior change; comments, docs, and @Test display names only

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Shared/Weekday.swift

@@ -19,7 +19,7 @@ enum Weekday: Int, CaseIterable, Codable, Hashable, Sendable {
     static let weekends: Set<Weekday> = [.saturday, .sunday]
     static let everyDay: Set<Weekday> = Set(Weekday.allCases)
 
-    /// Display order used by the day picker, matching the reference UI: S M T W T F S.
+    /// Display order used by the day picker: S M T W T F S.
     static let displayOrder: [Weekday] = [
         .sunday, .monday, .tuesday, .wednesday, .thursday, .friday, .saturday,
     ]