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>

AGENTS.md

@@ -3,8 +3,8 @@
 OpenAppLock is an iOS Screen Time app: recurring **rules** that block selected
 apps (Schedule windows, Time Limits, Open Limits), with a **Hard Mode** that
 makes an active block impossible to lift, edit, or delete until it ends. The
-feature set is a clone of Opal's "Rules"; the presentation is bare native iOS
-(List/Form/NavigationStack, default color scheme).
+presentation is bare native iOS (List/Form/NavigationStack, default color
+scheme).
 
 ## Repo layout
 
@@ -39,9 +39,9 @@ OpenAppLockShieldAction/    ShieldAction extension: Open press spends an open,
 OpenAppLockTests/               Swift Testing unit suites (@MainActor — the app
                             target defaults to MainActor isolation)
 OpenAppLockUITests/             XCUITest flows (see harness below)
-docs/RULES_FEATURE_SPEC.md  Feature spec derived from the Opal reference
-                            recording; §6 maps it to the native presentation.
-                            Review/update this BEFORE behavior changes.
+docs/RULES_FEATURE_SPEC.md  Feature spec for the rules behavior; §6 maps it
+                            to the native presentation. Review/update this
+                            BEFORE behavior changes.
 docs/SWIFT_GUIDELINES.md    Swift coding/testing/patterns/security standards
                             agents must follow on this project.
 ```
@@ -53,7 +53,7 @@ docs/SWIFT_GUIDELINES.md    Swift coding/testing/patterns/security standards
   *starts* on. `start == end` = 24h window.
 - Status is always **derived** (`rule.status(at:calendar:)`), never stored:
   `disabled / dormant / active(until:) / paused(until:) / upcoming(startsAt:)`.
-  Labels match the reference app ("6h left" rounds hours **up**).
+  Countdown labels round hours **up** (e.g. "6h left").
 - **Hard Mode**: `RulePolicy` is the single gate — while a hard-mode rule is
   actively blocking, canEdit/canDisable/canDelete/canUnblock are all false.
   Soft rules can be "unblocked", which sets `pausedUntil` = window end (the