Feature: Implement V0 Episodic Context Manager

- Re-wrote the monolithic string-based context manipulation logic into an elegant, immutable Episodic IR pipeline.
- Implemented four non-destructive degradation processors: `HistorySquashingProcessor`, `ToolMaskingProcessor`, `BlobDegradationProcessor`, and `SemanticCompressionProcessor`.
- Added dynamic configuration knobs (`budget` and `strategies`) to precisely tune the retention algorithms.
- Implemented a power-user `incrementalGc` flag for maximum context preservation beneath the ceiling.
- Enforced strict typing across the new pipeline, replacing unsafe casts with robust mapping interfaces.
- Added `powerUserProfile` to support features for those wanting a bit
  more quality at the cost of tokens.

schemas/settings.schema.json

@@ -2911,6 +2911,13 @@
           "default": false,
           "type": "boolean"
         },
+        "powerUserProfile": {
+          "title": "Use the power user profile for massive contexts.",
+          "description": "Enables continuous minimal GC near the max tokens limit instead of a blocked backbuffer.",
+          "markdownDescription": "Enables continuous minimal GC near the max tokens limit instead of a blocked backbuffer.\n\n- Category: `Experimental`\n- Requires restart: `yes`\n- Default: `false`",
+          "default": false,
+          "type": "boolean"
+        },
         "generalistProfile": {
           "title": "Use the generalist profile to manage agent contexts.",
           "description": "Suitable for general coding and software development tasks.",