refactor: unify request processing, archive completed specs, and remove legacy pytest compression

- Archive composite-model-routing and compression-layer specs to .kiro/specs/archive/
- Add unification-of-request-processing spec
- Refactor connectors (anthropic, hybrid, opencode_go) and orchestrator
- Simplify request_processor_service and remove legacy compression compatibility code
- Remove deprecated CLI arguments and session applicator features
- Update documentation: token-saving guide, config examples, schema cleanup
- Add tests for composite failure recovery bridge and routing state
- Clean up config schema by removing deprecated compression options

Author: Mateusz

…uting-failover-weighted-random/design.md …uting-failover-weighted-random/design.md.kiro/specs/composite-model-routing-failover-weighted-random/design.md renamed to .kiro/specs/archive/composite-model-routing-failover-weighted-random/design.md .kiro/specs/composite-model-routing-failover-weighted-random/design.md renamed to .kiro/specs/archive/composite-model-routing-failover-weighted-random/design.md

@@ -0,0 +1,51 @@
+# Gap Analysis: composite-model-routing-failover-weighted-random
+
+## Current Status
+
+- Requirements, design, and tasks are approved in `spec.json`.
+- Implementation status is complete and post-implementation polish has been applied.
+- Composite selector parsing, failover, weighted routing, and cross-surface routing are implemented through the shared routing entry point.
+
+## Post-Polish Alignment Update
+
+The following implementation gaps identified during deep code review were closed:
+
+1. **Explicit composite selectors no longer lose runtime failover in request processing**
+   - `BackendProcessor` now mirrors `BackendService` failover gating:
+     - explicit **non-composite** selectors disable runtime failover,
+     - explicit **composite** selectors keep runtime failover enabled.
+
+2. **Quality Verifier routing surface is deterministic**
+   - Quality verifier calls now stamp `composite_routing_surface=quality_verifier`.
+   - Surface resolution gives `call_purpose=quality_verifier*` precedence over stale surface hints.
+
+3. **Project directory LLM routing now allows composite runtime failover**
+   - Project-directory model calls now invoke backend execution with `allow_failover=True`.
+   - Unit coverage verifies failover-enabled invocation and composite-selector passthrough.
+
+4. **Replacement compatibility bridge now performs safe composite weighted translation**
+   - Safe legacy replacement selectors are translated into deterministic weighted composite selectors.
+   - Unsafe/ambiguous mappings still fail with explicit migration errors.
+   - N+1 deprecation metadata remains published.
+
+5. **Auxiliary routing ownership is consolidated**
+   - Duplicate auxiliary routing mutation logic in `RequestProcessorService` was removed.
+   - Canonical auxiliary routing adaptation remains in `BackendRequestPreparer`.
+
+## Requirements Coverage Snapshot
+
+| Requirement | Status | Notes |
+|---|---|---|
+| R1 Unified entry point | Implemented | Main/auxiliary/quality-verifier/replacement surfaces route through shared composite logic. |
+| R2 Failover selectors | Implemented | Ordered failover and deterministic exhaustion behavior are present. |
+| R3 Weighted selectors | Implemented | Weighted parsing/selection and default weights are covered. |
+| R4 Parsing/validation | Implemented | Deterministic parsing with mixed-operator rejection and validation errors. |
+| R5 Retry/failover safety | Implemented | Shared bounded attempt budget and meaningful-output guard enforced. |
+| R6 Backward compatibility | Implemented | Existing selector semantics retained for non-composite paths. |
+| R7 Replacement migration | Implemented | Deprecation metadata + compatibility bridge + explicit migration errors. |
+| R8 Observability/diagnostics | Implemented | Structured composite diagnostics available across supported surfaces. |
+
+## Validation Notes
+
+- Targeted unit/integration/regression test suites covering the touched areas passed after the polish changes.
+- Final full-suite and CLI end-to-end verification is executed in the verification phase after this document sync.

.kiro/specs/archive/composite-model-routing-failover-weighted-random/gap-analysis.md

@@ -1,7 +1,7 @@
 {
   "feature_name": "composite-model-routing-failover-weighted-random",
   "created_at": "2026-04-09T00:00:00+00:00",
-  "updated_at": "2026-04-09T19:03:00+00:00",
+  "updated_at": "2026-04-10T00:00:00+00:00",
   "language": "en",
   "phase": "implementation-complete",
   "approvals": {