docs(01): revise plan 03 wave + OffscreenLogger strict-mode per checker iteration 1

Two changes:
1. wave: 1 → 2 (cascade after Plan 02 wave fix)
2. OffscreenLogger: ...args: any[] → ...args: unknown[] for strict-mode
   hygiene. Existing Logger / ContentLogger are left on the legacy any[]
   pattern (refactoring is out of Phase 1 scope) — divergence documented
   via style_divergence_note frontmatter field.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.planning/phases/01-stabilize-video-pipeline/01-03-PLAN.md

@@ -2,7 +2,7 @@
 phase: 01-stabilize-video-pipeline
 plan: 03
 type: tdd
-wave: 1
+wave: 2
 depends_on: ["02"]
 files_modified:
   - src/offscreen/recorder.ts
@@ -10,6 +10,7 @@ files_modified:
   - src/shared/logger.ts
   - src/shared/types.ts
 autonomous: true
+style_divergence_note: "OffscreenLogger uses `...args: unknown[]` (strict-mode hygiene) where existing Logger / ContentLogger use `...args: any[]` (project convention). Refactoring the existing two for consistency is OUT OF SCOPE for Phase 1; they remain on the legacy pattern."
 requirements:
   - REQ-video-ring-buffer
 requirements_addressed:
@@ -519,20 +520,20 @@ export class OffscreenLogger {
     this.context = context;
   }
 
-  private logWithLevel(level: 'log' | 'warn' | 'error', ...args: any[]) {
+  private logWithLevel(level: 'log' | 'warn' | 'error', ...args: unknown[]) {
     const timestamp = new Date().toISOString();
     console[level](`[OS:${this.context}] ${timestamp}`, ...args);
   }
 
-  log(...args: any[]) {
+  log(...args: unknown[]) {
     this.logWithLevel('log', ...args);
   }
 
-  warn(...args: any[]) {
+  warn(...args: unknown[]) {
     this.logWithLevel('warn', ...args);
   }
 
-  error(...args: any[]) {
+  error(...args: unknown[]) {
     this.logWithLevel('error', ...args);
   }
 }