Align ash_ui with unified_dsl runtime architecture

[pcharbon70]

Summary

• re-baseline the specs, planning docs, and resource contracts around the unified_dsl architecture
• replace mock runtime binding paths with real Ash-backed reads, writes, lists, and actions
• harden LiveView lifecycle/reactivity, resource authorization, renderer selection, and conformance traceability

Stages Included

• Step 1: spec and planning re-baseline
• Step 2: real Ash-backed runtime bindings
• Step 3: LiveView reactivity and lifecycle hardening
• Step 4: authorization hardening
• Step 5: renderer selection and fallback hardening
• Step 6: conformance coverage, traceability, and reporting refresh

Verification

• mix test test/ash_ui/runtime
• mix test test/ash_ui/runtime test/ash_ui/liveview
• mix test test/ash_ui/authorization test/ash_ui/runtime test/ash_ui/liveview
• mix test test/ash_ui/rendering
• mix test test/ash_ui/conformance_traceability_test.exs test/ash_ui/telemetry_test.exs
• mix test test/ash_ui/compiler/incremental_test.exs test/ash_ui/compiler/phase_6_integration_test.exs
• ./scripts/validate_specs_governance.sh
• ./scripts/validate_code_docs.sh
• ./scripts/run_conformance.sh