Initial commit: AirCoding V1.0.0 Alpha architecture baseline

Complete architecture document set with multi-model review remediation:
- Frozen interface contracts, runtime semantics, DB schemas
- Event/tool/error/provider registries
- Scheduler and main agent state machines
- C4 module/code views, solution architecture, baseline V1
- Multi-model review reports and joint assessment
- Phase-gate remediation complete (P0/P1/P2/UX resolved)
- Implementation plan with T-000A through T-045
- Reference folders kept as placeholders only

AirPlan/docs/architecture/adr/ADR-0008-use-anthropic-canonical-messages-with-provider-adapters.md

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+# ADR-0008: Use Anthropic Canonical Messages With Provider Adapters
+
+- Status: Accepted
+- Date: 2026-05-27
+
+## Context
+
+AirCoding needs provider flexibility while preserving a stable internal representation for prompts, tools, messages, context compaction, and session persistence.
+
+## Decision
+
+Use Anthropic canonical content blocks internally. ContextAssembler emits Anthropic canonical messages. Provider adapters convert at the LLM boundary to Anthropic, OpenAI, OpenRouter, ollama, or compatible endpoints.
+
+Provider capability matrix controls whether a model can satisfy the task and whether conversion is lossless, lossy, or unsupported.
+
+## Consequences
+
+- Same-provider model switching has low conversion cost.
+- Cross-provider differences are localized to adapters.
+- Unsupported required features block before model call.
+- Tool/result/message persistence remains stable across providers.